Ingredients
Equipment
Method
Prep and blanch the Brussels sprouts
- Preheat oven to 400F, so it’s ready when the casserole is assembled. Keep a baking dish set aside for filling.
- Blanch Brussels sprouts 4 minutes in boiling salted water, then drain well. Look for bright green sprouts that are just starting to tenderize.
Make the creamy cheese sauce
- Cook bacon until crisp, then remove and reserve 1 tablespoon drippings. You should see browned, crisp pieces and a small amount of rendered fat in the pan.
- Melt butter with the drippings, add garlic and flour, and cook 1 minute. The mixture should look slightly thicker and smell fragrant.
- Whisk in milk and cream and simmer until thickened. Use a spoon to check—your sauce should coat and hold a line for a moment.
- Stir in 1 cup Gruyere, Parmesan, salt, and black pepper until smooth. The sauce should be glossy with no visible cheese clumps.
Assemble and bake
- Fold in Brussels sprouts and half the bacon, then pour into a baking dish. Spread into an even layer so it bakes uniformly.
- Top with remaining Gruyere, remaining bacon, and panko breadcrumbs. The top should look well covered and lightly speckled.
- Bake 20-25 minutes at 400F until bubbly and golden. Look for bubbling at the edges and a browned, crisp panko layer.
Notes
Pro tip: When simmering the sauce, keep it at a steady simmer and whisk often so the flour fully hydrates and the cheese melts into a smooth texture. Store leftovers covered in the refrigerator up to 3 days; reheat in the oven at 350F until warmed through. Freezing is not recommended because the creamy dairy can separate after thawing. For a dairy swap, use an equal amount of lactose-free milk and lactose-free cream, plus lactose-free shredded Gruyère and Parmesan if available.