Step 1: Preheat the Oven
Preheat your oven to 400°F (200°C). Spray a muffin tin with non-stick spray or grease lightly with butter.
Step 2: Mix the Ingredients
In a large mixing bowl, combine the mashed potatoes, beaten egg, and milk. Stir until smooth.
Add the cheddar cheese, Parmesan cheese, green onions, garlic powder, paprika, salt, and pepper. Mix well.
Step 3: Fill the Muffin Tin
Spoon the potato mixture into the prepared muffin tin, filling each cup about 3/4 full.
If using breadcrumbs, sprinkle a light layer on top of each puff for added crunch.
Step 4: Bake
Place the muffin tin in the preheated oven and bake for 20-25 minutes, or until the puffs are golden brown and slightly crispy on top.
Step 5: Cool and Serve
Let the puffs cool in the tin for 5 minutes before removing. Serve warm, garnished with extra chives or green onions if desired.