- 4 cups crusty baguette cut into 1-inch cubes
- 5-6 broccoli florets ~3 heads
- 1/2 large white onion diced
- 2 Tbs unsalted butter
- 2 Tbs all-purpose flour
- 2 cups milk
- 1 tsp kosher salt
- couple pinches fresh cracked pepper
- 1 tsp Dijon mustard
- 1/2 tsp prepared horseradish
- 1/2 tsp whole-grain mustard
- 1/4 cup mayonnaise see Notes
- 4 cups shredded cheddar cheese divided
- garnish: fresh basil leaves rolled up and sliced very thin
- Heat oven to 350F. If using fresh bread, put the cubed bread in the oven to very lightly toast for 10 minutes. If using day-old bread, do this for just 5 minutes or skip this step.
- In a 13×9 bake dish, add the broccoli, toasted bread cubes, and onion. Season with a pinch of salt and pepper.
- To a medium saucepan, add the butter and flour. Heat over medium-high, stirring until smooth, to make a roux. Slowly whisk in the milk and cook, stirring constantly, until milk starts to steam. Remove from the heat. Whisk in the Dijon, salt, pepper, horseradish, whole-grain mustard, and mayonnaise. Add half of the cheese, stirring until the cheese is mostly melted (does not have to be completely, and you can put back on the heat if necessary if it cools too much.)
- Pour cheese sauce over the broccoli casserole. Top with remaining cheese. Cover tightly with foil and bake at 350F for ~50 minutes or until broccoli is tender with a sharp knife inserted (see Notes). Remove foil and bake an additional 5 minutes. Serve topped with basil. Yields: 6 servings as a side; 4 as a main dish.