Miso-Cured Black Cod with Chilled Cucumbers

Ingredients

• ¾ pound skin-on black cod fillet
• Kosher salt

¾ cup white miso

• 3 tablespoons mirin
• 3 tablespoons sake
• 1 8x2-inch piece dried kombu
• 1 ounce shaved katsuobushi (dried bonito flakes; about 4 cups)
• 2 tablespoons unseasoned rice vinegar
• 4 teaspoons sugar
• 4 Japanese or Persian cucumbers

Kosher salt

• 1 1-inch piece ginger, peeled, cut into very thin matchsticks
• Find katsuobushi at Japanese markets or online.

Directions

1. Slice cod ¾” thick, leaving skin on and bones in (the bones will slip right out when fish is cooked). Season very lightly with salt and place on a paper towel–lined baking sheet. Cover with another paper towel and chill 1 hour (this will draw out some moisture and any fishy flavors).
2. Combine miso and mirin in a small bowl. Wet 2 paper towels (you can also use cheesecloth) with sake and squeeze out any excess. Spread half of miso mixture in a 13x9” baking dish in a thin, even layer. Cover with a sake-moistened paper towel. Arrange cod in a single layer on top. Cover with the other sake-moistened towel. Spread remaining miso mixture over towel. Cover; chill 3 days.
3. Preheat broiler. Transfer cod to a rimmed baking sheet; discard miso mixture and paper towels. Broil cod until golden brown around the edges and cooked through, about 4 minutes. Let cool slightly, then pull out bones.
4. Soak kombu in 2 cups cold water in a small saucepan at room temperature 2 hours, or chill up to 12 hours.
5. Bring to a bare simmer over medium heat. Discard kombu and bring liquid to a boil. Add katsuobushi; simmer 1 minute (reduce heat if needed). Strain through a paper towel or cheesecloth-lined sieve into a small bowl; discard solids. Let dashi cool.
6. Bring vinegar, sugar, and 2 Tbsp. water to a boil in a clean small saucepan. Remove from heat and stir to dissolve sugar. Let sweet vinegar cool.
7. Slice cucumbers in half lengthwise. If using Japanese cucumbers, scrape out seeds with a small spoon. Slice cucumbers into very thin half moons. Toss in a small bowl with a few pinches of salt. Let sit until salt begins to draw out water from cucumbers, about 5 minutes. Massage cucumbers, gently at first to keep them from breaking, then more vigorously as they start to expel water, until swimming in water. Rinse in several changes of water; squeeze out excess liquid. Place cucumbers in a clean small bowl and chill until cold, about 1 hour.
8. After cucumbers have chilled 30 minutes, place ginger and 1 cup water in a small bowl; soak 30 minutes to soften its pungency. Drain.
9. Add sweet vinegar and ¾ cup dashi to cucumbers (reserve remaining dashi for another use). Season with salt. Divide cod among shallow bowls. Top with cucumbers and ginger. Pour any cucumber liquid over.