Preheat oven to 400°F. Lightly grease a 24-cup mini muffin tin and set aside. In a large bowl, whisk together the mashed potatoes, beaten eggs, 3/4 cup of the shredded cheese, and chives until fully combined. Season with salt and pepper to taste. Use a small scoop or spoon to portion the potato mixture into the prepared muffin tin cups, filling them nearly to the top. Top each puff with the remaining 1/4 cup shredded cheese. Bake for 15-20 minutes until puffed, set, and lightly golden brown on top. Let cool for 5 minutes, then use a butter knife or offset spatula to gently remove the puffs from the tin. Serve warm, garnished with extra chopped chives and dollops of sour cream if desired. Enjoy! Notes Be sure to let any freshly made mashed potatoes cool completely before mixing in the eggs. Don’t overmix the potato mixture or it can become dense and gummy. Use a small cookie or portion scoop to easily fill the muffin tin cups. For crispier puffs, use a standard muffin tin instead of a mini one. Bake puffs on the lower oven rack for optimal browning. Let puffs rest for 5 minutes before removing from tin so they can set up.
