Rotel tomatoes are canned tomatoes with a little hint of heat. A Southern favorite, the spice comes from green chiles that have been fire-roasted, diced and stirred into the simmering tomatoes. Rotel tomatoes are a vital ingredient in queso and make a delicious addition to tortilla soup. The only downside to developing a dependency on Rotel tomatoes is that they can often be tricky to find if you live north of the Mason Dixon line, like I do.