Cook macaroni al dente according to package instructions. Drain, rinse and set aside.
In large saucepan, melt 3 tablespoons butter over medium heat. Blend in flour, stirring well to incorporate, and cook for an additional minute, stirring. Gradually whisk milk into butter and flour mixture. Cook, stirring constantly, until mixture comes to a boil and thickens. Over low heat, add salt, pepper and cayenne. Stir in 2 1/2 cups cheese, reserving remainder. Add cooked pasta to cheese mixture; stir well to combine.
Spread macaroni onto rimmed sheet pan to create even layer (about 1-inch thick). Allow to cool for at least 1 hour.
To prepare hot honey, place honey and hot sauce in small bowl and mix well to combine. Set aside.
Heat large skillet or griddle over medium-high heat. Cut mac and cheese into rectangles that match the size of the bread slices. Start with 1 bread slice and spread 2 tablespoons shredded gouda over. Place some macaroni over cheese. Drizzle with hot honey, top with additional 2 tablespoons cheese and second bread slice. Heat a skillet or grilled, butter outside of sandwich slices and grill 2-3 minutes per side, until cheese is melted and macaroni is warmed through. Repeat with remaining bread slices. Serve with additional hot honey.