Preheat oven to 275°; wrap flour tortillas in foil and warm in the oven.
Preheat a large nonstick skillet with the vegetable oil.
Add in the ground turkey and break it up with the back of a spoon as it cooks and browns, about 4 minutes.
Add in the onions, garlic, bell pepper, salt, and pepper; cook for 3 minutes.
Add in the chicken stock, pinto beans, and 1 ½ cup tomatilla salsa; increase the heat up to high; continue cooking 5-6 minutes or until the mixture is thickened.
Remove pan from heat and add in the cilantro; stir to mix.
Remove the flour tortillas from the oven and switch the broiler on.
Pile the turkey mixture into the warm tortillas; sprinkle each with ¼ cup cheese; roll up burrito style.
Line a casserole dish with the burritos, seam side down.
Top each burrito with a little bit of the remaining tomatillo salsa, spreading it over the burritos with the back of a spoon.
Sprinkle with the remaining cheese; place dish under the broiler, 6 inches from the heat source.
Broil for 5 minutes or so to melt and brown the cheese; serve immediately.