Spaceburger (Moses Lake)

I have not had a Spaceburger. It’s on the list, and this page is me doing the homework before the drive — because getting one takes planning. There are only two windows a year: five days at the Grant County Fair in Moses Lake, Washington every August, and one weekend in March. That’s it. The one place that sold them year-round closed in 2023.

And the first thing to know is that it isn’t a burger. It’s a sealed, crimped, crustless toasted sandwich — two slices of plain white bread with seasoned ground beef, a secret sauce, and shredded lettuce sealed inside and cooked, at about 400°F for thirty to forty seconds. The machine crimps the edges shut and cuts the crusts off, and what comes out is a disc with a raised rim. A flying saucer. That shape is where the name comes from.

Sealing the lettuce inside and steaming it is the genuinely strange part, and it’s not a detail you’d invent. Regulars order twenty at a time to freeze — and they order them without lettuce, because the lettuce is the part that doesn’t survive.

The machines are five 1962 originals from the Seattle World’s Fair, run by the Lioness Club as a community fundraiser. The recipe has not changed in fifty years and they will not tell anyone what’s in it — their own local paper tried and ran the story as “Sauce remains a mystery.”

So: the filling below is my reconstruction, not theirs. Two facts about the real one are on the record, and I built to those. Everything else is my invention and is labeled as such in the Notes. When I finally get to Moses Lake, this page gets rewritten with the real verdict.

Ingredients

• The filling — MY reconstruction, not the Lioness Club’s
• 1 lb ground beef, 80/20
• 1 small yellow onion, minced fine
• 2 Tbsp all-purpose flour
• 3/4 cup beef broth
• 1/4 cup ketchup
• 1 tsp yellow mustard
• 1 1/2 tsp kosher salt (see Notes — the real one is high in sodium)
• 1/2 tsp black pepper
• 1/2 tsp garlic powder
• 1/2 tsp onion powder
• The sandwich
• 16 slices plain white sandwich bread — soft, cheap, square
• Shredded iceberg lettuce

Softened butter, for the outside of the bread

• The tool (this is not optional — see Notes)
• A round pie iron, or a Toas-Tite

Directions

Key ingredients

Black Pepper · Salt · Mustard

1. First, the tool:
2. You cannot make this in a frying pan. The sandwich is defined by three operations happening at once — sealing the margins, compressing the crust, and toasting under pressure — and that needs a hinged iron. A round pie iron gives you the saucer shape; a square one works but makes a ravioli. A Toas-Tite is the historically correct device and is in production again. → photo 1
3. Make the filling — you want gravy, not crumbles:
4. Brown the beef in a dry skillet over medium-high, breaking it fine. Don’t drain it; the fat carries the roux. Add the onion and cook until soft, 4–5 minutes.
5. Sprinkle the flour over the meat and stir it in for a full minute — you’re making a roux in the pan fat. Then pour in the broth and stir until it thickens, another 2–3 minutes. Add the ketchup, mustard, salt, pepper, garlic powder and onion powder.
6. Simmer until it’s thick enough to hold its shape on a spoon and no liquid pools when you drag a line through it. This is the whole game. The one first-hand description of the real filling is a booth worker in 2008 calling it “a gravy-type thing with the meat” — so you’re after a bound, loose-meat, sloppy-joe texture, not dry crumbles and not soup. Anything runny will burst the seal. → photo 3
7. Cool it:
8. Let the filling cool to just-warm before you build. Hot filling steams the bread from the inside and softens it before it can toast, and it’s far more likely to blow the seam.
9. Build:
10. Butter one side of each slice of bread — that face goes against the iron. Lay a slice butter-side-down in the iron, press a shallow well in the middle, and add about 3 tablespoons of filling. Keep it well back from the edges; overfilling is the only real way to fail. Add a small pinch of shredded lettuce on top of the meat, then the second slice, butter-side-up.
11. Close it and mean it:
12. Close the iron and squeeze firmly. That squeeze is what welds the two slices together and trims the crust — a timid close gives you a sandwich that leaks. Trim any crust that squeezes out.
13. Cook:
14. Over medium heat, about 2–3 minutes a side, until deep golden. If you have a griddle you can hold at 400°F, the fair does 30–40 seconds — but their machine presses both faces at once with a thermostat and a thermal cutout, and yours doesn’t. Go by color, not the clock.
15. Rest briefly:
16. Give it a minute. The filling is molten and sealed in, which is exactly the hazard it sounds like.
17. If you’re freezing them:
18. Leave the lettuce out. That’s what the Moses Lake regulars do when they buy twenty, and they’re right — steamed lettuce doesn’t survive a freeze and thaw. Cool completely, wrap, freeze; reheat in the iron or a 350°F oven.

Notes

What this recipe is, and what it definitely isn’t

It is not the Moses Lake recipe. There isn’t a published one. The Lioness Club’s sauce and meat seasoning are a genuine secret, not marketing coyness — the Columbia Basin Herald ran an entire 2008 article headlined “Sauce remains a mystery” after the volunteers declined to tell their own local paper, and a 2024 regional piece still calls it “a closely guarded secret.” The sauce is mixed in giant batches at Chico’s Pizza Parlor in Moses Lake, because, per past president Frogg McMains, “they have the largest mixer of anybody in the community.”

Exactly two things about the real filling are on the record, and I built to both:

1. It’s gravy-textured. A booth worker in 2008: “I like that there’s no crust and they have a gravy-type thing with the meat.” That’s the single most useful physical description in any source — it means bound and thickened, not loose crumbles.
2. It’s high in sodium. McMains, on why she’s tried to change it: “we need to watch our sodium intake… I’ll get that done one of these days.” She also confirms the recipe hasn’t changed in fifty years.

Everything else in my ingredient list is mine. The ketchup, the mustard, the flour roux, the onion and garlic powder — none of that is documented. I chose a plain mid-century loose-meat gravy because that’s what the texture and the era point to. It is UNTESTED, by me and against the original. Do not repeat any of it as though it were theirs.

Two recipes circulating online under the name “Space Burger” are unrelated dishes and will send you wrong: a Budget101 recipe baking beef and barbecue sauce in biscuit cups in a muffin tin, and a Scandinavian 1980s burger with a pineapple ring. Neither has anything to do with Moses Lake.

The machine — the actually interesting part

The Spaceburger’s real ancestry isn’t hamburgers. It’s the sealed-sandwich iron, and that has a clean paper trail.

U.S. Patent 2,463,439, “Sandwich Grill” — filed 12 October 1945, granted 1 March 1949, inventor John E. Strietelmeier of Cincinnati, produced by Bar-B-Buns and sold as the Toas-Tite. The patent describes its own purpose as providing “a means for locating said filling in the center of the sandwich and for joining and sealing the marginal edges of the pieces by heat and pressure to preclude the escape of the filling.”

That is precisely the Spaceburger, patented seventeen years before the Seattle World’s Fair.

And it has a famous descendant. That same 1949 patent is the prior art that sank Smucker’s Uncrustables patent when it was reexamined in 2007. The sealed crustless sandwich was not a 1990s invention; a fair in Seattle was selling them in 1962 and a Cincinnati man had patented the mechanism in the 1940s.

The same principle in cast metal is the campfire pie iron and the Australian/South African jaffle iron. Toas-Tite sold from about 1949, left the market in 1953, and a replica returned to production around 2022 — so the handheld version was actually out of production in 1962, which fits: the fair used a larger purpose-built commercial machine instead.

The Moses Lake machines are five 1962 originals, maintained by David McMains, who describes them well: “Every so often with the old machines, you need to polish out the cups because they get a build-up of oil and bread… They’re 1962 models so they have a potentiometer, a sliding resistor that you can adjust. If the machine overheats, it shuts them off and then they’ll turn back on.” Cups, rheostat, thermal cutout — a purpose-built commercial sealer, not a griddle. They’re due for a rebuild. Five machines put out about 5,000 Spaceburgers a fair day.

Who made them is NOT FOUND. No manufacturer, no model name, anywhere. That’s the biggest technical gap in the story, and it’s a real one — the machines circulated to at least three states, so there was a product line and a salesman behind it, and nobody wrote the name down.

Where it came from

The 1962 Seattle World’s Fair (Century 21 Exposition) is where the machines and the concept start — a fair that also produced the Space Needle, opened during the Mercury program, five years after Sputnik. A 1987 Seattle Post-Intelligencer fairgoer’s recollection is the evidence, and it makes the shape the memorable thing: pressed “so that it looked like a flying saucer.”

Spaceburgers debuted at the Grant County Fair in 1964 and have run there since.

How the machines got to Moses Lake is openly a mystery. The best available account is a 1995 article in The Wenatchee World, which says members of the then-”Lady Lions” tracked down two of the machines gathering dust in people’s basements. Treat that as one 1995 newspaper claim, not settled fact — Atlas Obscura itself says flatly that how they arrived “remains a mystery.” And nobody has explained how two machines became five.

There is no inventor in the record. Not for the sandwich, not for the name. No source says who ran the 1962 fair concession, who coined “Spaceburger,” or why. The shape-plus-Space-Age reading is almost certainly right, but it’s inference — no document states it. Anyone who tells you it was named for the Space Needle or for Sputnik is guessing.

One independent thread confirms the machines were a commercial product: the Idaho State Journal reports that Kay Smith, founder of Tastee Treet in Pocatello, bought the machines from a salesman, and that they debuted at the 1962 fair and were not a Tastee Treet invention.

Where to actually eat one

Lioness Club of Moses Lake, Grant County Fairgrounds, 3953 Airway Dr NE, Moses Lake, WA. Two windows a year, and that is the whole list:

• Five days at the Grant County Fair, every August. 2026 dates appear to be 18–22 August, but that comes from fair-listing sites rather than the local paper — confirm before booking anything.
• One weekend in March. The 2026 booth ran 13–15 March, so the operation is current. The spring event is a survivor: the Spring Fair itself ended in 2012 and the booth weekend carried on without it.

About 5,000 a day at the August fair; the spring weekend does roughly half the fair’s total. They were $2.50 in 2008 and no recent article prints a current price.

⚠ Atlas Obscura’s page is out of date on this. It says Tastee Treet in Idaho sells Spaceburgers year-round. It closed permanently in April 2023 after 67 years, and the machines were auctioned off — the Idaho State Journal headline was “Sayonara Spaceburgers.” The Moses Lake club is now effectively the only seller, which is why the two-weekends-a-year thing matters.

Relatives

• Hawaii’s Flying Saucer — the closest living cousin, and the only one with a genuinely published filling recipe. Sandwich Tribunal’s Kauaʻi-style version: 1½ lb ground beef, 1 diced onion, 2 cloves garlic, 1 cup ketchup, 2 Tbsp sugar, 2 Tbsp soy sauce, a splash of water, salt and pepper — browned, simmered down, sealed in a Toas-Tite. Do not mistake this for the Moses Lake recipe. The soy and sugar are Hawaiian local-food signatures with no Washington evidence behind them, and it has no lettuce, which is definitional here.
• King’s Hat, Billings, Montana — uses “a more industrial looking machine acquired after the Seattle World Fair in 1962.” Same machine lineage, different state.
• Tastee Treet, Idaho — same machines, added cheese. Closed 2023.

Note the categories on this recipe deliberately exclude “Burgers.” It’s filed as a sandwich because that’s what it is, and the whole point of the page is that the family tree runs through the Toas-Tite, not the hamburger.

Still open

• The manufacturer of the 1962 machines. Nobody recorded it.
• Who ran the 1962 fair concession, and who coined the name.
• Two machines or five — the 1995 account and the present count don’t reconcile.
• The sauce. Still secret, and honestly it should probably stay that way.
• A Milwaukee Public Library historic-recipe item indexed as “Spaceburgers” that couldn’t be read through its viewer. Probably an unrelated mid-century Wisconsin novelty of the same name, but it’s the only institutional archive item bearing the word and deserves a manual look.

And the one thing only a trip fixes: whether my reconstruction is anywhere near it. August or March, Moses Lake.