Cook quinoa and rice in 1 cup of water, or according to package directions, for about 10 minutes. When done, fluff with a fork or spoon and stir in the cauliflower rice and allow it to sit, covered for 5 minutes.
Preheat the grill or grill pan. If you are using a cedar plank to cook your salmon, soak it in hot water.
Place the salmon filet on the cedar plank or on a piece of foil or grill sheet and cook it, with the lid down for 10 - 15 minutes, or until the salmon is done. (Tests 145℉ on an instant-read thermometer)
Remove the salmon from the grill and allow it to sit for 5 minutes. Then cut it into pieces and toss with ½ the teriyaki sauce.
While the salmon is cooking, heat oil in a small frying pan until sizzling. Add the mushrooms and let them brown (about 2 minutes), turn them and add the baby bok choy and stir gently to combine and wilt the bok choy.
Assemble the grain bowls
Place 1 cup of the grain and cauliflower mixture in a shallow bowl. Repeat with the rest of the grain in a second bowl.
Top each bowl with ½ the salmon, cooked mushrooms, and bok choy, peppers, and pineapple.
Drizzle with the remaining teriyaki sauce and top with pickled red onions if desired.