Dry salmon thoroughly with paper towel. Rub both sides of salmon with cayenne pepper, black pepper and sea salt. Allow salmon to sit at room temperature for 10 to 15 minutes. Please note, the surface of salmon will get moist again after salting. You should gently pat the salmon with a paper towel again, to remove moisture before cooking.

Combine Greek yogurt and Dijon mustard in a small bowl. Mix well and set aside.

Boil noodles according to directions. Rinse the boiled noodles under tap water, drain and set aside.

Add the oil into a nonstick skillet and place on medium high heat. When oil is hot, add Sichuan peppercorn and stir a few times until fragrant. Turn to low heat, carefully scoop out peppercorns with a spoon, and discard them. Turn back to medium high heat. (If you don’t use peppercorn, heat oil until hot before adding salmon.)

Place salmon into skillet, skin side down. Immediately press the filet against the skillet with a fish turner. (If you don’t have a fish turner, use a spatula to press against the thinner part of the fish) Hold the spatula for 20 to 30 seconds, until the skin part is cooked. Once the skin side has turned dark brown and crispy, after about 2 minutes, flip the salmon to cook the other side. If the salmon filet is thick, like the one in the picture below, you should cook the cut sides too, about 30 seconds on each. Adjust heat to medium or medium low, if the temperature of the skillet gets too high.

Insert a thermometer to test the temperature of the salmon. When the temperature registers 50 degrees C (120F), immediately transfer the salmon to a plate. Continue to cook the rest of salmon in the same manner. Quite a lot of grease will come out of the salmon during cooking, so you won’t need to add extra oil to cook the following pieces.

Place noodles on a large plate, add salmon on top, top with avocado slices, mustard yogurt and green onion. Serve immediately with mentsuyu. Drizzle mentsuyu on the noodles before eating. Pair the dish with a glass of dry white or dry sparkling wine.