Gruyere and caramelized onions are a pair that can make a fabulous grilled cheese sandwich or a classic French onion soup. This recipe for macaroni and cheese brings together the sweetness of the caramelized onions with the earthiness of Gruyere.
Cooking the onions in the béchamel helps the flavour really penetrate the sauce, so don’t do it separately! You can make this dish ahead of time, sprinkle it with cheese and refrigerate, it will reheat quite well in a 350F oven.
Caramelized Onion and Gruyere Macaroni & Cheese(serves 4)
Slice the onion in half and then in thin slices against the grain. Heat a large saucepan to medium and add the oil, onion and a pinch of salt. Carefully sauté the onions until a nice deep brown, don't be afraid to adjust the heat if the onions are burning or not browning. Add the butter and stir to melt. Once melted stir in the flour and cook, stirring for 3 minutes. Slowly add in milk, stirring to incorporate. If you do this too fast it will be lumpy. Add 1/2 cup at a time at before stirring to allow the mixture to simmer together first. Once all the milk has been added, add the bay leaf and let the mixture simmer gently for 10 minutes stirring regularly so it doesn't burn to the bottom. Taste and season.
Cook the macaroni until al dente, reserve 2 cups of the pasta water and drain. Stir cheese slowly into sauce reserving a tablespoon or two of the top. Add pasta, and stir in just enough pasta water to coat all of the pasta with the sauce. Taste and season again. Transfer to a casserole dish and sprinkle with remaining cheese. Turn on your broiler and broil until bubbly and brown on top.[