Preheat and Prepare
Preheat your oven to 400°F (200°C).
Grease a 9-inch pie dish with butter or cooking spray.
Prepare Filling
Mix diced ham, grated Swiss cheese, and chopped yellow onion in a large bowl.
Make Batter
Whisk together beaten eggs, whole milk, dry biscuit mix, salt, garlic powder, onion powder, and pepper in a separate bowl until smooth.
Combine Filling and Batter
Pour the egg mixture over the ham, cheese, and onion mixture in the large bowl. Stir gently to combine evenly.
Bake
Spread the mixture evenly into the prepared pie dish.
Bake in the preheated oven for 35-40 minutes, or until the top is golden brown and the center is set.
Cool and Serve
Let the pie cool for a few minutes before slicing.
Serve warm and enjoy!
