The "caldo" is a Mexican (not Tex-Mex) soup made of broth. There is a big feature about these dishes in today's Dallas Morning News. Caldo Tlalpeno sounds particularly delicious. I am sure that one could add as much heat to it as one wanted. Check it out. Unusual. I grew up here, and I must admit that I never heard of this "caldo" term before. Be sure to click on "Related Stories, Caldo Recipes" on the right. Roberto http://dallasnews.com/lifestyles/food/34425_CALDO.html