Prep. Preheat oven to 425˚F. Grease a 9x13 casserole dish with cooking spray and set aside.
Make the chicken filling. Heat 1 tablespoon olive oil in a skillet; add shredded chicken and cook just until heated through. Remove from heat, stir in 1 cup shredded cheese, and distribute the chicken mixture evenly among the flour tortillas.
Roll up the tortillas. Roll up the tortillas and place them seam-side down in the casserole dish. Set aside.
Sauté the peppers. Heat 1 tablespoon olive oil in a skillet. Add diced peppers and season with salt; cook for 2 minutes or until tender, stirring occasionally. Remove the peppers from the skillet and set aside.
Make the sauce. Add butter to the skillet and let it melt over medium-high heat. Stir in flour and continue to stir until moistened. Whisk in the chicken broth and continue to whisk until the sauce is smooth and thickened. Stir in the yogurt and prepared peppers; season with salt, pepper, Italian seasoning, and 1/2 tablespoon fresh parsley. Mix and stir until thoroughly combined.
Add the sauce to the rolled tortillas. Remove from the heat and pour the sauce over the rolled tortillas.
Bake. Sprinkle the remaining cheese over the tortillas and bake for 20 to 25 minutes or until bubbly and golden on top.
Finish and serve. Remove the enchilada casserole from the oven and let it cool for 7 to 10 minutes. Garnish with fresh parsley or cilantro and serve.
Notes
Warm your tortillas. Do this either one by one on a skillet or wrap them in foil and warm them in the oven at 350˚F for 15 minutes. This will help to make them more pliable.
Avoid overfilling tortillas because this can cause difficulties when rolling and may lead to tearing.
Roll enchiladas tightly. This helps to keep them intact during baking.
Ensure even sauce coverage. Evenly spread the sauce to boost flavor and prevent the enchiladas from drying out in the oven.
Cooked shredded chicken: If you want a different protein, cooked shredded turkey, chopped shrimp, or tofu could work well.
Shredded Italian Cheese Blend: You can use shredded mozzarella, provolone, or a blend of both. I used Sargento's Shredded 6 Cheese Italian Blend. For a different flavor, try shredded cheddar or Monterey Jack.
Flour tortillas: If you want a different type of wrap, you could use whole wheat tortillas, low-carb flour tortillas, or gluten-free tortillas.
Bell pepper: You can also consider using yellow or green bell peppers for a different flavor. Other vegetables like sliced mushrooms, diced zucchini, tomatoes, or spinach will also work.
Storage: Cool leftovers to room temperature, place in an airtight container, and store in the fridge for up to 4 days. Freezing isn't recommended due to the yogurt sauce, which may become grainy upon defrosting, but if necessary, cool completely, store in an airtight container, and freeze for up to 3 months. Thaw in the fridge before reheating.