Combine the bell peppers, onions, and garlic together in a deep microwave safe dish. Combine the chile powder and cumin powder in a bowl and add the chicken, turning to coat. Place the sliced chicken over the vegetables, and cover with plastic wrap. Microwave the chicken and vegetables on high for 12 to 15 minutes. The internal temperature of the chicken should read 165 degrees F when done cooking.
Place the tortillas on a microwave-safe plate cover with damp paper towels and microwave for about 30 seconds to warm. Serve the chicken, vegetables, and warm tortillas alongside the sour cream and salsa.