This is the best Yellow Squash Casserole! Thinly sliced fresh squash is combined with sautéed bacon and onion, cheese, crackers, and a buttery egg mixture. Perfect as a side, Sunday brunch, or holiday get togethers!
Preheat oven to 400 degrees F. Coat a 9x9 square baking dish with nonstick spray; set aside.
Using a mandolin (if possible) slice the squash into 1/8-inch thin rounds; transfer to a large bowl.
In a large skillet, sauté bacon over medium heat until starting to get crispy, about 6 minutes. Add in the onion and continue to cook until soft and translucent, about another 2-3 minutes. Stir in the garlic and cook until fragrant, about 20 seconds. Season with a sprinkle of salt and pepper. With a slotted spoon, transfer mixture to the bowl with the squash.
In a small bowl, mix together the crushed crackers and cheese; add half of the mixture in with squash and bacon. Stir gently to combine.
In another bowl, whisk together the eggs, milk, salt, pepper, and melted butter. Pour over the squash. Mix to combine, making sure all the squash slices get coated.
Spread into the prepared pan; sprinkle with the remaining cracker and cheese mixture. Dot with the cold butter bits.
Bake until lightly browned, 25-30 minutes. Let sit for a few minutes before serving and enjoy!