Rinse the quinoa thoroughly in a fine-mesh strainer, then combine with 6 tablespoons of water in a small saucepan. Bring to a boil, then reduce heat to low, cover, and simmer for 12-15 minutes until the water is absorbed and the quinoa is fluffy.
While the quinoa cooks, slice the chicken breast into bite-sized strips. In a small bowl, mix the chili powder, cumin, cayenne pepper, sea salt, and black pepper.
Toss the chicken strips in the spice mixture until evenly coated.
Heat the olive oil in a large skillet over medium-high heat. Add the chicken and cook for 5-7 minutes, turning occasionally, until golden brown and cooked through.
Remove the chicken from the skillet and set aside. In the same skillet, add the sliced bell peppers and red onion. Sauté for 3-4 minutes until they are tender-crisp and slightly charred.
Warm the black beans in a small pot or in the microwave.
Assemble the bowl by placing the cooked quinoa at the base. Top with the spiced chicken, sautéed peppers and onions, and black beans.
Drizzle the entire bowl with lime juice and garnish with freshly chopped cilantro before serving.