Preheat the oven to 400°F.
In a medium size mixing bowl, mix together the mashed potatoes, garlic & herb cheese, 1 cup shredded cheese, eggs, Parmesan cheese, 1 Tbsp chopped chives, garlic salt, and black pepper. Mix well breaking up the garlic & herb cheese to evenly distribute.
Brush the cups of a 12 cup standard muffin tin liberally with cooking spray or melted butter. Use a 4 oz ice cream scoop to divide the mixture between the cups,
Sprinkle the tops with the remaining shredded cheese.
Place into the oven and bake for 23-25 minutes or until set and the tops are golden.
Run a knife around the edges to loosen.
Serve with or without a dollop of sour cream and garnish with the remaining chopped chives.