Stir 3/4 cup picante sauce, sour cream and chili powder in a medium bowl.
Stir the picante sauce mixture, chicken and cheese in a large bowl.
Spoon about 1/3 cup chicken mixture down the center of each tortilla. Roll up the tortillas and place seam-side up in a lightly greased 11 x 8-inch shallow baking dish. Pour the remaining picante sauce over the filled tortillas. Cover the baking dish.
Bake at 350 6;F. for 40 minutes or until the enchiladas are hot and bubbling. Top with the onion.
TIP Easy Substitution: Substitute 3 cans (4.5 ounces each) Swanson® Premium White Chunk Chicken Breast in Water, drained, for the cooked chicken.