In a resealable, gallon-sized plastic bag, mix lime juice, garlic, chili powder, salt, cumin, and oil until well-combined.
Add chicken, seal bag, and knead to coat evenly.
Let marinade 30 minutes - 6 hours (I don’t recommend more than 6 hours as the acid from the lime juice can break down the chicken, affecting its texture).
Heat your griddle to medium-high heat and cover the surface with olive oil. Add the peppers and onions to half your griddle and cook for 2-3 minutes, turning occasionally.
Add the chicken and marinade mixture to the other half of your griddle and cook for 8-10 minutes, turning occasionally. Cook until the chicken’s internal temperature is 165 degrees.
Serve on tortillas, top with cheese, sour cream, guacamole, and tomatoes.
