Place the chicken breasts in the bottom of a slow cooker (4-quart or larger).

In a small bowl, whisk together the taco seasoning mix and chicken broth until well combined.

Pour the seasoning mixture over the chicken in the slow cooker. Add the lime juice.

Cook on low for 6 hours or on high for 3-4 hours, until the chicken is cooked through and easily shredded.

Remove the chicken from the slow cooker and shred it using two forks. Return the shredded chicken to the slow cooker and toss to coat in the liquid.

Approximately 30 minutes before serving, heat the olive oil in a large skillet over medium-high heat. Add the sliced bell peppers and onion. Sauté for 5-7 minutes until softened and slightly charred.

Stir the cooked vegetables into the slow cooker with the seasoned chicken and let everything heat through for the final 30 minutes.

Warm the flour tortillas according to package directions (microwave or skillet). Serve the chicken fajita mixture immediately with warmed tortillas and your favorite toppings.