Cheesy Spinach Dream Boat Casserole Easy Comfort Food -…

Ingredients

• 2 tablespoons unsalted butter (30ml)
• 1 medium yellow onion, finely chopped (approx. 1 cup)
• 2 cloves garlic, minced
• 1/4 cup all-purpose flour (30g)
• 2 cups whole milk (475ml)
• 1/4 teaspoon nutmeg
• 1/2 teaspoon salt
• 1/4 teaspoon black pepper
• 300g (10.5 oz) frozen spinach, thawed and squeezed dry
• 1 cup grated mature cheddar cheese (115g)
• 1/2 cup grated Gruyere cheese (57g)
• 1/4 cup grated Parmesan cheese (28g)
• 1 cup sour cream (240ml)
• 1/2 cup mayonnaise (120ml)
• 1/2 cup panko breadcrumbs (30g)
• 2 tablespoons melted butter (30ml)