Heat vegetable oil in a medium skillet over medium heat. Add chopped bell peppers and onion, sautéing until softened.
Remove from heat and transfer to a large mixing bowl.Add shredded chicken and cheese and toss to combine.
Spray a 9x13 baking dish with cooking spray.
Evenly divide chicken mixture between the flour tortillas, rolling tight and fitting snuggly into the baking dish. If you are making this dish ahead of time, stop here and refrigerate until ready to cook.
Top burritos with green enchilada sauce and 1 cup cheese sauce. You might have some cheese sauce left over for dipping tortilla chips.
Bake, uncovered, for 15-20 minutes or until edges of tortillas start get brown and toasty.Remove and top with freshly shredded cheese, jalapenos and tomatoes.
For cheese sauce:
Heat butter and flour in a small saucepan over medium heat. Whisk together to form a paste.Add milk, whisking until smooth, still over medium heat.
Add shredded cheese, whisking until smooth.
Continue to whisk while adding salt.
Continue to cook until cheese sauce starts to thicken, then remove from heat. If you like a thicker cheese sauce, this should be good, but if you wanted something a little thinner, add 1-2 tablespoons more milk until you reach your desired consistency.
If you've tried this recipe, come back and let us know how it was!
*you can use chopped leftover chicken or buy a precooked rotisserie chicken at the grocery store and shred it. Alternately, you can use canned chicken.