It does NOT get better than this. This is SUPER rich and cheesy. Not for the faint of heart! Dinosaur BBQ's mac and cheese has been featured on tv and in magazine's as the best mac and cheese in the country. I think they are right.
Heat oil in a large pot. Add onions and peppers; cook until they are translucent. Add garlic and cook until fragrant. Stir in flour. Add water and half-and-half. Bring to a boil. Reduce heat to a simmer and cook for 10 minutes.
Using an immersion blender, puree this mixture until it is smooth (*if using a regular blender, work in batches, filling the pitcher only half-full, since the liquid will be hot). Slowly add cheeses to warm pureed mixture, making sure all cheese is melted before adding more. Once cheese is completely melted, add salt, lemon pepper, sugar, mustard, vinegar and Tabasco. Stir to combine.
Cook 1 1/2 pounds of dried elbow macaroni in boiling water, according to manufacturer's instructions. Cook until al dente, not completely soft.
Combine hot, cooked pasta and sauce in large mixing bowl; stir well to combine. Pour entire mixture into a greased 10-inch-by-12-inch pan (or a 9-inch-by-13-inch one). Top with 8 ounces. of shredded cheddar cheese and 2 tablespoons of Pecorino Romano cheese.
Place under broiler until top is golden brown and bubbling. Serve immediately.