Macaroni, Broccoli and Cheese Casserole

1. Bring a large pot of lightly salted water to boil. Cook macaroni for 1 minute less than al dente according to the package directions. Add broccoli 3 minutes before the macaroni is finished. Drain macaroni and broccoli and return to the pot.

2. Preheat oven to 375 degrees F (190 degrees C).

3. Meanwhile, melt butter in a large saucepan over medium heat. Add bread crumbs and cook, stirring often, for 2 minutes or until light golden brown. Transfer to a small bowl, mix with 1 tablespoon parmesan cheese, and set aside.

4. In the same saucepan, whisk together milk and flour until blended, then add onion. Bring to a boil over medium-high heat, whisking frequently. Reduce heat to low and simmer for 2 minutes or until thickened. Remove from heat and whisk in cheddar cheese, mustard, salt, black pepper, and remaining 2 tablespoons parmesan cheese.

5. Pour sauce over the macaroni and broccoli and mix well to combine. Transfer to a baking dish and evenly sprinkle the top with bread crumbs.

6. Bake for 20 to 25 minutes or until the casserole is bubbly at the edges.