This is a wonderful recipe for macaroni and cheese. I, however, have not made it with the topping. Please let me know if you use the topping and if you like it.Ingredients:1/2 lb. elbow macaroni3 tbsp. butter3 tbsp. flour1 tbsp. powdered mustard3 cups milk1/2 cup chopped yellow onion1 bay leaf1/2 tsp. paprika1 large egg12 oz. sharp cheddar cheese, shredded1 tsp. kosher saltfresh black pepperTopping:3 tbsp. butter1 cup panko bread crumbsDirections:Preheat oven to 350 degrees.In a large pot of boiling, salted water cook the pasta to al dente.While the pasta is cooking, in a seperate pot, melt the butter. Whisk in the flour and mustard and keep it moving for about 5 minutes. Make sure it is free of lumps. Stir in the milk, onion, bay leaf and paprika. Simmer for 10 minutes and remove the bay leaf.Temper in the egg. Stir in 3/4 of the cheese. Season with salt and pepper. Fold the macaroni into the mis and pour into a 2 quart casserole dish. Top with remaining cheese.Melt the butter in a saute pan and toss the bread crumbs to coat. Top the macaroni with the bread crumbs. Bake for 30 minutes. Remove from oven and rest for five minutes before serving.