Lightly coat the inside of a 5–6 quart slow cooker with nonstick cooking spray.

Arrange the boneless, skinless chicken breasts in an even layer in the bottom of the slow cooker.

Sprinkle the taco seasoning, kosher salt, and cracked black pepper evenly over the chicken.

Pour the diced tomatoes and green chilies, including their juice, over the chicken. Add the diced green chiles.

Cover and cook on high for about 4 hours, or until the chicken is fully cooked and reaches an internal temperature of 165°F (74°C).

Use two forks to shred the cooked chicken directly in the slow cooker.

Pour the salsa con queso over the shredded chicken. Stir until the chicken is thoroughly coated and creamy. Use slightly less queso if you prefer a thicker filling.

Spoon the Queso Chicken Tacos filling into street taco-size flour tortillas.

Top with shredded lettuce, diced tomatoes, chopped cilantro, and sour cream as desired. Serve warm.