3tablespoonsunsalted butter, plus more for greasing the pan
1/2small onion, finely chopped
1/4teaspoonsweet paprika
1/4teaspoonground cayenne pepper
1/4teaspoonground nutmeg
1/8teaspoonground allspice
Freshly ground black pepper
1/4cupflour
3cupswhole milk
1/4poundBrie, rind removed
1/4poundGruyère, shredded
4ouncesbacon, cooked and chopped into 1/2-inch pieces
1large Granny Smith apple, chopped in 1/2-inch pieces
1/2cupwalnuts, toasted and coarsely chopped
3tablespoonsshredded Parmesan cheese
Instructions
Preheat an oven to 375°F. Grease an 8 x 8-inch baking dish (or a small rectangular dish) with butter and set aside.
Cook the pasta in a large pot of salted, boiling water just 1 minute shy of the timing listed on the package instructions. Drain and set aside.
In a large skillet or saucepan, melt the butter over medium heat. Add the onion with a pinch of salt, and cook, stirring occasionally until soft (4 to 6 minutes). Stir in the paprika, cayenne, nutmeg, allspice and several turns of black pepper, and cook for 2 minutes. Increase the heat to medium-high, whisk in the flour, and cook for 1 minute. Add half of the milk, stirring and whisking frequently, until thickened (3 to 5 minutes), and then repeat with the other half of the milk. I like to use a whisk if I see any lumps. Otherwise, I stir with a spoon or spatula. Add the Brie and Gruyère, stirring until the cheese is completely melted. Take the skillet off the heat, and stir in the cooked shells, bacon and 3/4 of the chopped apple. Season to taste with salt and pepper.
Pour the mixture into the prepared baking dish and top with walnuts, Parmesan and reserved apple. Bake until the top is browned and the sides are bubbling (about 25 minutes). Cool for 5 minutes, then enjoy!