Brussel Sprouts Casserole

Bahan-bahan (8 porsi)

• 3 slices thick-cut bacon
• 2 pounds brussels sprouts
• 1/2 yellow onion (finely diced)
• 3/4 teaspoon kosher salt (divided)
• 1 tablespoon unsalted butter
• 2 tablespoons all-purpose flour
• 1 1/2 cups 2% milk
• 1 tablespoon chopped fresh thyme (or 1 teaspoon dried thyme leaves)
• 1/4 teaspoon ground black pepper
• Pinch ground nutmeg (optional)
• 1/2 cup freshly grated Gruyère cheese (sharp white cheddar cheese, or a similar fully flavored, melty cheese)
• 1/4 cup whole wheat bread crumbs
• Olive oil cooking spray