Questions about Mac and Cheese

Saturday night dinner is supposed to be all about easy right? Not this time. I had planned a different meal but it was super easy and I could make it ahead of time for a weeknight. Instead, I decided to have some pulled pork from the freezer, make some coleslaw, then some homemade sheet pan mac and cheese. Realistically this recipe only goes on the sheet pan for 10 minutes... so I'd have been WAY more impressed with it if you actually make the entire thing on a sheet pan. This recipe is good - I thought it was good. Andy - too creamy - Bronwyn and Nicholas - It's not the blue box... so I ate it... ate too much of it... and likely will be the only who eats it. Something is wrong with my family - they need to learn about good food.
Bernard... now he'd eat it with me - if given a chance. But let's not give him that chance right?

Sheet Pan Mac and Cheese

1 pound large elbow macaroni
4 tablespoons unsalted butter
2 cloves garlic, minced
1 medium shallot, minced
1/4 cup all-purpose flour
1 teaspoon paprika
2 cups whole milk
1 cup heavy cream
2 teaspoons Dijon mustard
Kosher salt and freshly ground black pepper, to taste
16 ounces extra-sharp cheddar cheese, grated
1/2 cup freshly grated Parmesan
1 cup Panko

In a large pot of boiling salted water, cook pasta according to package instructions; drain well.
Preheat oven to broil on high. Arrange an oven rack 6-inches from the broiler. Lightly oil an 18 x 13-inch sheet pan or coat with nonstick spray.
Melt butter in a large skillet over medium high heat. Add garlic and shallot, and cook, stirring frequently, until fragrant, about 2 minutes.
Whisk in flour and paprika until lightly browned, about 1 minute. Gradually whisk in milk, heavy cream and Dijon until slightly thickened, about 3-4 minutes. If the mixture is too thick, add more milk as needed; season with salt and pepper, to taste.
Remove from heat. Stir in 2 1/2 cups cheddar cheese, Parmesan and pasta until well combined; season with salt and pepper, to taste.
In a small bowl, combine Panko and remaining cheddar cheese.
Spread pasta mixture into the prepared sheet pan; sprinkle with Panko mixture.
Place into oven and broil, rotating the sheet pan a few times, until golden brown and crispy, about 5-6 minutes.
Serve immediately.