Place chicken in a pot and put enough water to just cover the top of the chicken meat. Simmer the chicken until tender, which should be about 20 minutes. Let cool. Skin and de-bone the chicken, using your fingers. Be sure to get only the meat and none of the skin or gristle. Shred or chop the meat into small sugar cube size pieces. Take the broth that is left and put it into the refrigerator so the fat will rise to the top. You want to let the broth get cold, which will let you scoop the fat off of the top so you are de-fatting the broth.
While you are waiting for the broth to de-fat itself, get a small skillet, add the corn oil, onion & bell pepper and cook just until the onion becomes translucent which is about 5 to 7 minutes. When it is cooked, turn off the heat and add the shredded chicken, mix well and then set aside.
Take the broth out of the refrigerator and remove the fat, which has come to the top. You need 2 & 1\2 cups of the broth. Be sure that the broth is just liquid. Set aside and make the sauce.
For the sauce, melt 1\4 cup of butter in a small saucepot over medium heat. Whisk in 1\4 cup of flour and cook about one minute. Whisk in the 2 & 1\2 cups of broth till it gets hot and then add 1 tablespoon of ground cumin, 1 teaspoon of salt, 1 teaspoon of black pepper, 1 teaspoon of garlic powder and 2 tablespoons of finely chopped fresh jalapeno pepper. Cook until it thickens, then whisk in 1 cup of sour cream and cook for 1 minute and remove from heat.
Spoon just enough of the sauce into the chicken mixture to bind. Then fill each tortilla with the chicken mixture, roll-up the filled tortilla and put into an ovenproof baking dish, seam side down. Cover with remaining sauce and the cheese and bake for about 20 minutes at 350 degrees until the sauce is bubbly and brown. Makes six servings.