Cook the brown rice according to package instructions and let it cool slightly until it is warm but not hot.
Dice the fresh salmon fillet into even 1/2-inch cubes and place them in a medium glass bowl.
In a small mixing bowl, whisk together the tamari, rice vinegar, grated fresh ginger, and sesame oil to create the marinade.
Pour the marinade over the salmon cubes and gently toss to ensure every piece is coated; let it marinate for 5 to 7 minutes.
Thinly slice the cucumber and radishes into rounds, and finely chop the scallion.
Place the cooked brown rice at the bottom of a serving bowl.
Top the rice with the marinated salmon cubes, sliced cucumbers, radishes, and shelled edamame.
Drizzle any remaining marinade from the salmon bowl over the top.
Finish the bowl by garnishing with chopped scallions, sesame seeds, and red pepper flakes for a touch of heat.