Heat the oven to 450ºF. Arrange the bell peppers cut-side up in a broiler-safe pan. Bake until slightly softened, 6 to 10 minutes. Remove from the oven. Turn broiler to high.

Combine water and quinoa in a medium saucepan; bring to a boil over high heat. Cover and cook until the liquid is absorbed, about 15 minutes.

Meanwhile, heat the sesame oil in a sauté pan set over high heat. Add the tofu and cook 2-3 minutes per side, or until deeply browned. Stir in the cooked quinoa and the remaining ingredients.

Spoon 1/2 cup of filling into each pepper half. Broil until warmed through and starting the brown, about 5 minutes.