Mix 4 tbsp ponzu sauce, 1 tbsp mirin and 1 tbsp sake in a bowl and set by the stove ready for later.
Pat 2-3 salmon fillets dry with kitchen paper and sprinkle both sides with 1 pinch salt and pepper.
Coat the salmon with a thin, even layer of 1 tbsp potato starch.
Heat a pan on medium and melt 1 tbsp unsalted butter. Swirl the pan around and place the salmon fillets in with the skin-side facing down. Fry for 4 minutes or until the skin is crispy and golden.
Flip and fry on the other side for 2 minutes. (Add an extra 1-2 minutes if your salmon fillets are especially thick.) Remove the salmon from the pan and set aside.
In the same pan, add 30 g bell pepper(s) and 50 g maitake mushrooms. (Add a little more butter if necessary.) Sauté until the bell peppers are slightly softened.
Once softened, push the bell peppers and mushrooms to one side of the pan and place the salmon back in the pan with the skin side facing up. Pour the ponzu sauce around the pan and occasionally baste the top of the salmon. Once the sauce becomes glossy and slightly thickened, remove from the heat.
Plate up 300 g cooked multigrain rice and place 50 g baby leaf salad on top. Add the sautéed vegetables and then the salmon.
Drizzle any sauce leftover in the pan over the salmon and sprinkle with 1 tsp sesame seeds for a finishing touch.
Enjoy!