French Onion Mac & Cheese
French Onion Mac & Cheese is WAY better than the soup.
- 5 tbsp. butter, divided, plus more room temperature for brushing
- 2 large yellow onions, thinly sliced
- Kosher salt
- 8 oz. cavatappi or other short curly pasta
- 2 tbsp. all-purpose flour
- 2½ c. whole milk
- 1 c. grated fontina cheese
- 2½ c. grated Gruyère
- 1 c. shredded sharp white cheddar
- 1 tsp. Dijon mustard
- Pinch of cayenne pepper
- 1 tsp. fresh thyme leaves, plus more for garnish
- Preheat oven to 350°. Brush 4 to 6 ramekins (depending on size) or small ovenproof baking dishes with butter. Alternatively, brush one large baking dish with butter.
- In a large skillet, melt 3 tablespoons of the butter over medium. Add the onions and a pinch of salt and cook, stirring occasionally, until they are golden, about 30 minutes.
- Cook pasta in a large pot of boiling salted water, following package directions until al dente. Drain pasta.
- In a medium saucepan, melt the remaining 2 tablespoons butter over medium-high. Add flour and cook, stirring, 1 minute. While whisking, slowly pour in milk until combined. Bring to a boil and reduce heat to medium. Simmer, stirring, until sauce is thickened, about 6 minutes. Stir in fontina, 1 cup of the gruyere, and cheddar until cheese is melted. Remove from the heat. Stir in the pasta, caramelized onions, Dijon, thyme, and cayenne. Season with salt and pepper.
- Divide mixture among ramekins and top each ramekin with the remaining gruyère. Bake until sauce is bubbly around the edges, about 20 minutes.
- Switch oven to broil and broil until cheese is golden, about 2 minutes. Garnish with more thyme before serving.