2 sticks butter
2 onions, finely chopped
5 heaping tbsp. flour
3 c. milk
1 or 2 cans Rotel tomatoes (to taste)
10 oz. can green chilies
2 lbs. Velveeta cheese

Fry onions in butter over very low heat or in double boiler. Add flour. Add milk stirring continously. Add tomatoes, green chilies, and cheese. Stir frequently until cheese melts. Serve in slow cooker to keep cheese melted.