If the thought of tongue excites you -- gastronomically speaking, that is -- then we suggest you try the stewed version at Ruchi's Taquerias El Rincon de Mexico [2651 Richmond, (713)520-6523, and other locations]. It is available in a taco (99 cents), a torta ($2.50) or a burrito ($2.75). Not the least bit stringy, tongue has a firm, dense, spongy texture that, because it almost springs back in your mouth, can feel a little eerie. All three dishes have the same basic ingredients: shredded lettuce, chunks of avocado, diced tomatoes and sour cream. Your decision ultimately boils down to one question: How much tongue do you like?