I like to make a roux with flour and butter, add milk, and melt real cheese. Sometimes I'll add just a little Velveeta as well. From there, add your Rotel, or just get crazy with whatever fresh veggies you want. Adding ground sausage is a favorite of mine.
1lb. Hamburger
1lb. Spicy ground sausage
1 can diced green chili
1 can cream of mushroom soup
Fill empty soup can w/ milk and add
1 chopped onion or dried onion flakes
1 block of velveta
Garlic powder to taste (I usually go on the heavy side)
Salt and pepper to taste