Grilled Mac and Cheese Sandwich

Instructions:

Make the mac and cheese 1. Bring a medium saucepan of generously salted water (you want it to taste like seawater) to a boil. Add the pasta and cook, stirring occasionally, until al dente, 8 to 10 minutes, or according to the package directions. The pasta should be tender but still chewy. 2. While the pasta is cooking, in a small bowl, whisk together the flour, mustard powder, garlic powder, salt, black pepper, and cayenne pepper. 3. Drain the pasta in a colander. Place the empty pasta pan (no need to wash it) over low heat and add the butter. When the butter has melted, whisk in the flour mixture and continue to cook, whisking frequently, until the mixture is beginning to brown and has a pleasant, nutty aroma, about 1 minute. Watch carefully so it does not scorch on the bottom of the...