Follow package directions for preparing pasta (approximately 6-9 minutes' cooking time).
2. While pasta is cooking, make the sauce:
3. Melt butter in a large skillet over medium heat.
4. Add minced garlic to melted butter. Saute one minute.
5. Add flour, mustard powder, and cayenne pepper to melted butter and sauteed garlic. Combine using a whisk.
6. Add evaporated milk to flour mixture. Whisk to combine until no lumps of flour remain.
7. When mixture begins to bubble and thicken, add Swiss/Gruyere cheese wedges. Continue whisking until the wedges melt. Do not allow the mixture to boil.
8. Add remaining cheeses. Whisk until smooth. The sauce should coat a wooden spoon but should not be stringy or difficult to stir. If it is, add half-and-half or milk and whisk until the sauce is smooth and reaches the desired thickness.
9. Return cooked, drained pasta to its original cooking pot. Add cheese sauce and combine with pasta using a rubber spatula. Serve immediately.