Step 1

Pat 1 lb. large shrimp, peeled, deveined, dry; sprinkle with 1 tsp. Diamond Crystal or ½ tsp. Morton kosher salt and season with freshly ground black pepper. Thinly slice 6-8 scallions (depending on their size and your preference); set some dark green parts aside for serving.

Step 2

Heat 2 Tbsp. extra-virgin olive oil in a large skillet over medium-high. Arrange shrimp in a single layer; cook, undisturbed, until a golden brown crust forms underneath, 1–2 minutes. Turn over and cook until pink and opaque, about 30 seconds. Transfer to a plate.

Step 3

Heat 2 Tbsp. unsalted butter in same skillet over medium until foaming, then add scallions, 8 garlic cloves, thinly sliced, ¼ tsp. crushed red pepper flakes, and ½ tsp. Diamond Crystal or ¼ tsp. Morton kosher salt. Cook, stirring occasionally, until scallions and garlic are softened, about 3 minutes. Add ¼ cup dry white wine, scraping up any brown bits with a heatproof rubber spatula, and cook until almost completely evaporated. Add 2 Tbsp. soy sauce and 1 Tbsp. doenjang (Korean fermented soybean paste) or 2 Tbsp. light miso and cook, stirring constantly, until doenjang is dissolved. Remove from heat.

Step 4

Add two 8–9-oz. blocks frozen Sanuki udon noodles to a large pot of boiling water and cook, undisturbed, 20 seconds. Using tongs, gently release from caked state. Cook until tender, about 45 seconds (no more than 1 minute). Drain, reserving 1 cup udon cooking liquid.

Step 5

Transfer half of shrimp to a cutting board and cut into thirds. Return to plate with remaining shrimp.

Step 6

Return skillet with scallion mixture to medium-low heat. Add ½ cup udon cooking liquid and remaining 2 Tbsp. unsalted butter; stir until a homogenized sauce forms. Return shrimp and any accumulated juices to pan and toss to combine. Add udon and toss again, adding more reserved cooking liquid if needed, until sauce is glossy and coats noodles; season with salt.

Step 7

Divide shrimp scampi udon among plates, making sure to place a few whole shrimp on top. Finely grate some zest from 1 lemon over. Top with reserved scallion greens; season with black pepper. Cut lemon into wedges and serve alongside for squeezing over.