Preheat the oven to 350° F.

Spray a 9x13-inch baking dish with nonstick cooking spray. Set aside.

Place two sheets of paper towels on a large plate. Set aside.

Place a large skillet over medium-high heat. Add the bacon and fry until brown and crisp, flipping once, 6-8 minutes.

Transfer the bacon to the paper-towel-lined plate. Do not discard the bacon fat.

Return the skillet to the heat and add the thawed hash brown potatoes. Cook, stirring occasionally with a rubber spatula, until slightly golden brown, 4-5 minutes. Remove from heat.

In a large mixing bowl, whisk together the eggs, milk, salt, and black pepper.

Using clean hands, crumble the bacon into small pieces and add to the egg mixture. Add the potatoes and shredded cheese. Fold with a rubber spatula to evenly distribute.

Pour the mixture into the prepared baking dish.

Bake the casserole on middle rack of oven until top is golden brown and a toothpick inserted in the center comes out clean, 40-45 minutes.

Check to see that casserole is done. Remove from oven or add time as needed.

Allow casserole to cool for at least 10 minutes before serving. Cut the casserole into squares, or simply spoon onto plates.