Directions

1. Bring a large pot of lightly salted water to a boil. Cook elbow macaroni in the boiling water, stirring occasionally, until tender yet firm to the bite, about 8 minutes. Drain and set aside.
2. Meanwhile, melt butter in a large skillet over medium-high heat. Whisk flour in gradually until smooth. Cook and whisk continually for 2 minutes. Add mustard, salt, pepper, cayenne, and garlic; stir to combine. Gradually whisk in half-and-half and milk. Cook, whisking continually, until thickened, 8 to 10 minutes. Add 9 ounces Gouda cheese and stir. Add chevre and 1 ounce blue cheese and stir until smooth. Remove skillet from heat. Stir cooked macaroni into cheese mixture.
3. Set an oven rack about 6 inches from the heat source and preheat the oven's broiler.
4. Divide macaroni and cheese into 6 greased 6-inch cast iron skillets. Top each with corned beef, sauerkraut, a drizzle of Thousand Island dressing, and equal amounts of remaining Gouda and blue cheeses.
5. Broil skillets in the preheated oven until cheese is golden brown, 3 to 5 minutes.
6. Toast rye bread in a toaster and cut each slice diagonally into points. Serve rye bread with Reuben mac.