Queso Fundido

I had planned to share this lovely warm barley salad I made last week with you guys, but since I got back from Texas, one thing has dominated my thoughts: queso.
Queso; that gooey, warm dip made mostly of cheese with a little chili and tomato for extra flavor. Northern friends might call it nacho cheese. The Texan version is ubiquitous at Tex Mex places, parties, and on every appetizer menu. The key to a good Texan queso is to use processed cheese or velveeta. There really is no other way to get that particularly gooey, creamy texture.