Heat oven to 350°. Combine first five ingredients in a large mixing bowl. Add half a can of cream of mushroom soup. Melt 1 tablespoon butter in the bottom of a 13x9x2-inch baking dish. Fill tortillas with chicken mixture; sprinkle with hot sauce to taste. Roll tortillas and place seam side down in prepared baking dish. Melt 2 tablespoons butter in a saucepan and mix with 1½ cans of soup. Pour over enchiladas. Bake, uncovered, for 30 minutes until golden brown. Garnish with sour cream and avocado slices, if desired. May be served with rice and beans. Yields 10 servings.