Step 1

Combine lime juice, soy sauce, Worcestershire, 1 tablespoon olive oil, garlic, cumin, chili powder, and red pepper flakes in a shallow glass or nonreactive dish just large enough to hold chicken in one layer or so it's covered in marinade. Whisk to combine. Add chicken and turn several times to coat; cover, and refrigerate for 1 to 3 hours.

Step 2

Remove chicken from marinade, reserving at least 1/4 cup.

Step 3

Heat 1 tablespoon of olive oil in a skillet over medium-high heat. Cook chicken until no longer pink in the center and juices run clear, 7 to 10 minutes. Rinse the skillet and wipe dry with a paper towel.

Step 4

Heat remaining olive oil in the skillet over medium-high heat. Add bell peppers and onion and cook, stirring frequently, until tender and lightly charred, about 5 minutes. Return chicken to the skillet, drizzle in 2 to 4 tablespoons of reserved marinade, and cook over high heat until marinade is heated thoroughly, at least 1 minute. Season with salt and pepper. Serve immediately with warmed flour tortillas.