Set your oven to 400°F (200°C).
Line your baking sheet with parchment paper.
This prevents sticking and makes cleanup easy.
Put mashed potatoes in a large bowl.
Add cheddar cheese, flour, and eggs.
Mix everything together well.
Add green onions and garlic powder.
Season with salt and pepper.
The mixture should be thick and sticky.
Use a cookie scoop or spoon.
Make small balls about golf ball size.
Place them on your prepared baking sheet.
Leave space between each puff.
They will spread slightly while baking.
Sprinkle Parmesan cheese on top of each puff.
This creates a crispy, golden crust.
Press it down gently so it sticks.
Bake for 20-25 minutes.
They should be golden brown and crispy.
The cheese will be bubbling and delicious.
Let them cool for 5 minutes before serving.