4 slices bacon, diced
2 cups vegetable oil, or more, as needed
3 cups leftover mashed potatoes
1 cup shredded cheddar cheese
2 tablespoons chopped fresh chives
1/2 teaspoon cayenne pepper, optional
2 large eggs, beaten
1 1/2 cups Panko*
2 tablespoons freshly grated Parmesan
Heat a large skillet over medium high heat. Add bacon and cook until brown and crispy, about 6-8 minutes. Transfer to a paper towel-lined plate; set aside.
Heat vegetable oil in a large stockpot or Dutch oven over medium high heat.
In a large bowl, combine mashed potatoes, cheese, chives, cayenne pepper and bacon.
Using a small cookie scoop, roll the mixture into 1 1/4-to-1 1/2-inch balls, forming about 25.
Working one at a time, dip balls into eggs, then dredge in Panko, pressing to coat.
Working in batches, add balls to the Dutch oven and cook until evenly golden and crispy, about 2-3 minutes. Transfer to a paper towel-lined plate.
Serve immediately, garnished with Parmesan, if desired.