Preheat your oven to 400°F (200°C). Grease a 9-inch pie dish thoroughly with butter or cooking spray.

In a large skillet over medium heat, cook the ground beef and chopped onion together for 6-8 minutes, breaking up the meat with a wooden spoon until the beef is completely browned and the onion turns soft and translucent. Drain any excess fat.

Season the beef mixture with salt, pepper, garlic powder, and Worcestershire sauce if using. Stir well and cook for another minute. Spread the seasoned beef mixture evenly across the bottom of your prepared pie dish.

Sprinkle the shredded cheddar cheese evenly over the beef layer, distributing it to the edges.

In a mixing bowl, whisk together the eggs, milk, and flour until completely smooth with no lumps. The batter should be thin and pourable, about the consistency of heavy cream. Pour this mixture slowly and evenly over the beef and cheese.

Bake for 25-30 minutes or until the top turns golden brown and the center is set when you give the dish a gentle shake. A knife inserted in the center should come out clean.

Let the pie rest for 5-10 minutes before slicing to allow the layers to set properly.