Mashed Potato Puffs

Cook's notes: I have used this pan to make cake, cupcake and cornbread squares. And now I can add to the list... mashed potato puffs. But any cupcake pan will work just fine for this recipe.
Leftover mashed potatoes get a new lease on life thanks to these puffs! They're combined with eggs, sour cream, cheese and chives then baked in a cupcake pan until golden and crusty with creamy middles. They don't taste like leftovers. But if no leftovers-no problem make a batch of mashed potatoes the day before and then asemble the recipe next day. 
These puffs make a great side for roasts, salmon and fish. 
Recipe makes 8 and was adapted from cinnamonspiceandeverythingnice.com

Mashed Potato Puffs

Ingredients:

• 2 eggs
• 1/3 cup sour cream, plus more for serving
• 1 heaping cup shredded sharp cheddar cheese
• 2 tablespoons grated Parmesan
• 2 tablespoons chopped chives
• 1 tsp. parsley flakes
• salt and black pepper, to taste
• 3 cups mashed potatoes

Directions:

• Preheat oven to 400 degrees. Grease 8 - 9 of the wells of a non-stick cupcake pan.
• In a medium mixing bowl whisk the eggs, then whisk in the sour cream. Mix in both cheeses and the chives.
• Add in mashed potatoes, salt and pepper to taste and mix well.
• Spoon potato mixture into the cupcake wells just to the top or a little below.
• Bake 25 - 35 minutes until they pull away from the sides of the cup and are golden brown all over.
• Remove from oven and let them cool 5 minutes in pan. Turn them out onto a platter. Serve with sour cream.

Grate frozen butter straight into pastry dough for fast, even distribution.

Caramelize onions in half the time by adding a little baking soda.

You can read the full explanation of how this works at Serious Eats.