Adjust rack to top position and preheat oven to 450 degrees. Bring a medium pot of salted water to a boil. Wash and dry produce. 

Trim and thinly slice cucumber into rounds. Peel and mince or grate ginger. Trim and thinly slice scallions, separating whites from greens. Zest and quarter lime. Roughly chop peanuts. Roughly chop cilantro. 

Once water is boiling, add noodles to pot. Cook, stirring occasionally, until al dente, 5-7 minutes. 

Drain and set aside. (Reserve pot for Step 5.)

In a small bowl, combine vinegar, ½ tsp sugar, ½ tsp salt, and pepper until sugar and salt are mostly dissolved (use 1 tsp sugar and 1 tsp salt for 4 servings).

Add cucumber and toss to thoroughly combine. Refrigerate until ready to serve. 

Pat salmon* dry with paper towels; drizzle with oil and season all over with half the turmeric (all for 4 servings), salt, and pepper.

Place salmon, skin sides down, on a foil-lined baking sheet and coat with chili sauce. Roast on top rack until salmon is cooked through, 8-10 minutes. 

Heat a drizzle of oil in pot used for noodles over medium-high heat. Add scallion whites; cook until fragrant, 30-60 seconds.

Whisk in miso sauce concentrates, ½ cup water, 1 TBSP butter, 1 tsp cucumber pickling liquid, ½ tsp sugar, and as much lime zest as you like (1 cup water, 2 TBSP butter, 2 tsp cucumber pickling liquid, and 1 tsp sugar for 4 servings). Cook, whisking constantly, until sauce has thickened, 1-2 minutes. 

Remove pot from heat; add drained noodles and toss until fully coated. Taste and season with salt and pepper if desired. 

Divide noodles, salmon, and pickles (draining first) between shallow bowls in separate sections. Spoon ginger scallion oil over salmon. Squeeze lime over noodles. Top everything with peanuts and cilantro. Serve with any remaining lime wedges on the side.