Preheat your oven to 400°F (200°C).

In a large skillet, heat over medium heat, add the ground beef and chopped onion. Sauté until the beef is browned and the onion is softened, about 5-7 minutes.

Season the beef and onion mixture with salt, black pepper, garlic powder, and Worcestershire sauce if using. Stir for 2 minutes.

Grease a 9-inch pie dish with cooking spray or butter. Spread the seasoned beef mixture evenly across the bottom.

Sprinkle shredded cheddar cheese over the beef mixture.

In a mixing bowl, whisk together the eggs, milk, and all-purpose flour until smooth.

Pour the egg mixture evenly over the cheese and beef layers in the pie dish.

Bake in the preheated oven for 25-30 minutes until golden brown.

Remove the pie from the oven and let it cool for about 5-10 minutes.

Slice the pie into wedges and serve warm.