Preheat oven to 350 degrees. Meanwhile, sautee onions in butter.

Combine butter and onions with chicken in bowl with cream cheese, cumin, and a little milk.

Wrap chicken mixture in tortillas and place in baking dish.

Make sauce by combining soup, sour cream, and remaining milk. Pour over totillas and chicken.

Bake for 35 minutes, covered. Cover with shredded cheese and bake uncovered for about 5 minutes or until cheese is melted.