Baked Macaroni and Cheese

I found this recipe on Food Networks site and altered it just a little.
Just a little FYI at the end of this recipe they said "be sure to save leftovers for fried mac and cheese" oh goodness do we really need to go there?

Ingredients

• 1/2 pound elbow macaroni
• 3 tablespoons butter
• 3 tablespoons flour
• 1 tablespoon powdered mustard
• 3 cups milk
• 1/2 cup yellow onion, finely diced
• 1 bay leaf (optional, I didn't have a bay leaf on hand so I left it out)
• 1/2 teaspoon paprika
• 1 large egg
• 12 ounces sharp cheddar, shredded
• 1 teaspoon kosher salt
• Fresh black pepper

Topping:

• 3 tablespoons butter
• 1 cup panko bread crumbs (love panko bread crumbs! They are cheap and they use them in a lot of weight watchers recipes, find them in the hispanic foods isle. You can use regular bread crumbs if you want though.)

Directions

Preheat oven to 350 degrees F.

In a large pot of boiling, salted water cook the pasta to al dente.

While the pasta is cooking, in a separate pot, melt the butter. Whisk in the flour and mustard and keep it moving for about five minutes. Make sure it's free of lumps. Stir in the milk, onion, bay leaf, and paprika. Simmer for ten minutes and remove the bay leaf. (So we put the bay leaf in and then take it out...glad I didn't run to the store for it.)

Stir in the egg. Stir in 3/4 of the cheese. Season with salt and pepper. Fold the macaroni into the mix and pour into a 2-quart casserole dish. Top with remaining cheese.

Melt the butter in a saute pan and toss the bread crumbs to coat. Top the macaroni with the bread crumbs. Bake for 30 minutes. Remove from oven and rest for five minutes before serving.