Preheat your oven to 400°F (200°C).

In a large skillet over medium heat, add the ground beef and chopped onion. Cook for about 6–8 minutes, stirring occasionally, until the beef is browned and the onion is softened.

Add salt, black pepper, garlic powder, and Worcestershire sauce to the skillet. Stir well and let the mixture cook for an additional 2 minutes.

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

Sprinkle a generous layer of shredded cheddar cheese evenly over the beef mixture.

In a mixing bowl, whisk together the eggs, milk, and all-purpose flour until smooth. Pour this mixture evenly over the cheese and beef layers in the pie dish.

Place the pie in the preheated oven and bake for 25–30 minutes, or until the top is golden brown.

Allow the pie to cool for about 10 minutes before slicing and serving warm.