Preheat oven to 400F. Process cheese and jalapeno in food processor till chopped in 1/4" pieces. Add butter, pulse on and off till size of small peas. Stir flour with cornmeal, salt, chili powder and mustard in small bowl till blended. Add to mixture in processor, pulse on and off just till blended. Sprinkle water evenly over mixture in processor. Pulse on and off just till dough begins to form into a ball. Shape dough into 8" disk. Wrap in plastic wrap; refrigerate till firm enough to roll, about 30 minutes. On floured surface, roll dough to 1/4" thickness. Cut in 2" rounds with cookie cutter or wine glass. Transfer to ungreased baking sheet. Prick each cracker once with fork. Bake in preheated oven for 10 to 12 minutes or till crisp. Transfer to rack to cool. Store in airtight container. Makes 50 crackers.