1. Preheat your oven to 400°F (or 375°F if using convection). Line a large baking sheet with parchment paper or lightly grease it.

2. Heat the olive oil in a large skillet over high heat for 1 to 2 minutes. Add the chicken tenderloins and cook for about 3 minutes on one side. Flip and cook another 3 to 4 minutes, until golden brown and cooked through. Remove the chicken from the skillet and set aside.

3. If the pan looks dry, add a small drizzle of oil and reduce the heat to medium-low. Add the sliced red bell pepper and red onion. Cook for about 12 minutes, stirring often, until the peppers are soft and tender.

4. Return the chicken to the skillet. Remove from heat and stir in the red pesto until everything is evenly coated.

5. Slice each garlic baguette lengthwise, cutting almost all the way through so it opens like a book. Place the baguettes on the prepared baking sheet and bake for 7 minutes to lightly crisp.

6. Remove from the oven and spoon the chicken and vegetable mixture evenly into each baguette. Top generously with shredded cheese, spreading it in an even layer.

7. Return to the oven and bake for 5 to 6 more minutes, until the cheese is melted and lightly golden.

8. Let cool slightly, then slice each baguette into halves or thirds before serving.