Skip the store-bought packets and make your own homemade Fajita Seasoning! It's incredibly simple and can be mixed together in minutes (and you can reduce or omit the salt and the sugar if you want to).
In a small bowl, combine chili powder, cumin, paprika, sugar, garlic powder, onion powder, cayenne pepper to taste (I like 1/2 teaspoon), and salt to taste (I like 1 teaspoon). Store in an airtight container.
Paprika: Both sweet and smoked paprika work here.
Sugar: Leave this out if you want to.
Cayenne pepper: Add more if you like spicy food, omit entirely if you don't.
Yield: This recipe makes 1/4 cup fajita seasoning which is enough to season 4 pounds of beef, chicken, or shrimp.
Storage: Store this spice blend covered in the pantry for up to 6 months.
Making chicken fajitas:
In a plastic bag, add 2 pounds chicken (breasts or thighs), 1/4 cup minced cilantro, 3 tablespoons lime juice, and 2 tablespoons of fajita seasoning. Mash until evenly coated. Marinate at least 30 minutes (room temperature) or up to 1 hour (refrigerated).
In a large skillet over medium-high heat, heat 2 tablespoons olive oil until shimmering. Add chicken and cook until crispy and browned on one side, about 8 minutes. Flip and cook until browned on the second side and chicken registers 160 degrees, about 8 to 10 minutes longer. Transfer chicken to a cutting board and rest for 5 minutes before cutting into strips (do not discard fat in skillet).
Meanwhile, to the skillet with the fat over medium-high heat, add 3 bell peppers (sliced) and 1 red onion (sliced) and cook until tender, about 5 minutes. Push peppers and onions to one side and add sliced chicken back to skillet for serving. Serve with tortillas, avocado, cilantro, and sour cream (or your favorite toppings).