Heat oil in a large skillet over medium heat; add peppers, onions and celery and cook until tender. Add garlic and chicken broth. In a separate skillet, cook and drain sliced sausage. Add sausage to vegetable mixture. Start sprinkling in cheese, stirring to melt. Add cheese until queso is the desired thickness. Stir in chopped tomato. Serve queso with chips as an appetizer, or, over smoked potatoes, baked potatoes, sauteed spinich, broccoli, fried potatoes or noodles.