Vidalia Onion Casserole - a creamy, cheesy sweet onion filling is topped with a buttery cracker crumb topping to make a fantastic spring side dish casserole.
Cut the ends off the onions. Place each one flat side down and cut in half.Place each onion half flat side down and cut in half again so that you have quartered the onion. Now cut each piece in ¼ to ⅓-inch slices.Note: You could also dice the onion using a large dice. You just want the pieces to be cut up enough that it is easy to eat the casserole, but big enough that the pieces still have some substance to them.
Place onion in a pot and cover with water. Bring to a boil for 5 minutes. Drain well.
Melt butter in a large skillet. Add onion and cook over medium heat for 5 minutes. Set aside.
Preheat oven to 350 degrees and grease a 9x13-inch casserole dish.
In a large bowl, whisk together eggs and evaporated milk. Mix in Ritz crackers, cheddar cheese, Parmesan cheese, salt, pepper and onions.
Transfer mixture to prepared baking dish.In a small bowl combine cracker crumbs and melted butter for topping. Sprinkle on top of casserole.