Melt butter. Add flour. Mix well and cook over moderate heat for about 1 minute.
2
Add canned tomatoes. Cook over moderate heat, stirring constantly until mixture thickens.
3
Stir in chopped green chilies and shredded cheese. Continue stirring over moderate heat until cheese is melted.
4
I sauce is took thick, add milk until the desired consistency is reached
5
Keep warm until served by placing in top part of a double boiler.
6
To serve, spread tortilla with chili con queso sauce, roll and eat out of hand. Or tortilla can be broken into bite size pieces and dipped into warm sauce.