Preheat oven to 250 degrees.

Heat 2 teaspoons oil in a small pan over medium heat and add pancetta.

Cook pancetta, stirring frequently until it's just browned and crispy.

Drain pancetta on a paper towel lined plate and let cool to room temperature.

Combine mashed potatoes with pancetta, egg, cheddar, chives, salt and pepper (mixture will be little loose).

Heat remaining oil in a large non-stick sauté pan over med/high heat until hot, but not smoking.

Using a medium ice cream scoop, scoop out portions of potato mixture and place into hot oil (you will need to cook in two batches).

Press down on each scoop to flatten slightly and cook until browned, about 2 minutes.

Carefully flip each potato pancake and cook on the other side until browned and cooked through, another 2-3 minutes.

Place pancakes on a paper towel lined sheet pan and hold in warm oven until ready to serve.

Serve with creme fraiche or sour cream and chives if desired.