Start by preheating your oven to 350°F (175°C). This allows the casserole to cook evenly and develop that golden top we all love.
In a large pot, bring water to a boil and add the diced squash. Don't forget to add a pinch of salt. Cook the squash for about 10 minutes or until tender. Drain and set aside. This helps to remove excess water and enhances the casserole's texture.
In a skillet over medium heat, melt a tablespoon of butter. Add the chopped onion and sauté until translucent, approximately 5 minutes. This step enhances the onion's sweetness and contributes to the dish's overall flavor profile.
In a large mixing bowl, combine the cooked squash, sautéed onions, sour cream, mayonnaise, beaten egg, and 1 cup of cheddar cheese. Add salt and freshly ground black pepper to taste. If you opted for the garlic powder and smoked paprika, toss those in as well. Mix well to ensure all the ingredients are blended together.
In a greased baking dish, pour the mixed ingredients. Spread evenly. Then, in another bowl, combine the crushed Ritz crackers with the melted butter. Stir until the crumbs are evenly coated.
Sprinkle the buttery cracker mixture over the top of the casserole. Then, sprinkle the remaining ½ cup of cheddar cheese on top for that extra cheesy goodness. Place the dish in the preheated oven and bake for 30-35 minutes or until it’s golden brown and bubbling.
Once out of the oven, allow the casserole to cool for a few minutes. Then dig in! This dish is best enjoyed warm and pairs perfectly with your chosen sides.