Cut the fresh salmon fillet into bite-sized pieces.

Mix miso, mirin, and white sesame seeds in a bowl. Coat the salmon pieces with the mixture.

Cut the komatsuna into bite-sized pieces and tear the maitake mushrooms into small chunks. Place them in a microwave-safe container.

Combine frozen corn, dried sakura shrimp, and mayonnaise in a microwave-safe container.

Place the containers with salmon, komatsuna mixture, and corn mixture on a baking tray. Bake in a toaster oven for about 7 minutes until the salmon is cooked through.