Preheat the oven to 425 degrees F. Line a baking sheet with parchment paper or lightly grease a 12-inch cast iron skillet. Use a knife to cut butter into pea-sized pieces. Transfer to the freezer to keep cold while you prep the remaining ingredients.
Combine all dry ingredients (flour, baking powder, salt, garlic powder, white sugar) in a medium mixing bowl. Stir in the pea-sized pieces of cold butter. Use your fingers to make the butter even smaller as needed, like you would with regular biscuits.
Pour in the milk. Use a wooden spoon to stir until the batter is mostly holding together. It will still be wet and a little sticky. Fold in the shredded cheddar and sliced green onions.
Use a cookie or ice cream scoop to scoop 8-9 biscuits out onto the baking sheet or cast iron. Keep about 1/2 inch between biscuits. Bake at 425F for 14-16 minutes, or until golden. Enjoy!
Flour: Spoon and level flour into the measuring cup for best results. To do this, use a spoon to scoop flour into your measuring cup until overflowing. Use the back of a knife to wipe off excess flour.
Butter: Salted butter can be used but omit the 1/2 teaspoon of salt.
Leftovers: Store at room temp in a closed container for 2-3 days. To freeze, place in a freezer-safe bag for up to 3 months. Reheat in the microwave until thawed.
White vs whole wheat: This recipe can be made with 100% white or 100% whole wheat if desired. The texture will be slightly different in both cases but will yield a very similar biscuit.