Bring medium saucepan of water to a boil; add the brown rice and boil 10 minutes. Stir in quinoa and cook until both grains are tender, about 15 more minutes. Drain well and set aside.
Meanwhile, drizzle bell peppers with 1 tablespoon water in a microwave-safe bowl. Cover with plastic wrap; microwave 10 minutes.
Heat olive oil in a wide saucepan over medium-high heat. Add onion and cook, stirring, until golden, about 5 minutes. Add sausage, garlic, thyme, allspice and 1/2 teaspoon salt and cook, stirring, until sausage is brown and crisp, about 3 more minutes. Add tomatoes and 1 cup water to pan. Pile the kale on top, cover and cook until kale wilts, about 2 minutes. Stir kale into sauce and bring to a simmer. Arrange the bell peppers on top, cover and simmer until the kale is just tender, about 8 minutes.
Divide the peppers among plates. Stir the grains into the kale mixture and season with salt. Spoon into the peppers. Top with parsley.