Preheat oven to 350°F (175°C) and line a large baking sheet with a non-stick silicone baking mat or parchment paper.

In a medium mixing bowl, combine the shredded chicken, sugar-free BBQ sauce, chopped cilantro, and minced red onion until the protein is uniformly coated.

Place the mozzarella slices on the prepared baking sheet, ensuring at least one inch of space between each slice to allow for expansion.

Bake for 5 to 7 minutes or until the edges of the cheese slices are golden brown and the centers are bubbling.

Remove the baking sheet from the oven and allow the cheese to cool for approximately 60 seconds until it is firm enough to handle but still pliable.

Distribute the chicken mixture evenly, placing approximately 2 tablespoons of filling along the edge of each cheese slice.

Carefully roll the cheese slices around the filling to form a cylinder and place each taquito seam-side down on a serving plate.

Let the taquitos rest for 3 minutes to allow the cheese shells to fully crisp before serving.