This savory, meaty comfort food classic is a traditional St. Patrick's Day dish! Ground lamb is cooked with herbs and vegetables, sprinkled with cheddar cheese and topped with a luscious layer of mashed potatoes made with our Potato Flakes! To make this a cottage pie, use ground beef instead of lamb.
Heat water to boiling, then add butter and salt. Remove from heat and add cold milk. Add potato flakes and stir gently. Fluff with a fork; do not whip. Let sit for 2–3 minutes to thicken before serving. Set aside.
Preheat oven to 400°F.
Heat oil over medium heat in a deep 10–12-inch ovenproof skillet. Add onion, carrot and minced garlic and cook until just soft, 5–7 minutes. Add lamb and cook until browned, 3– 5 minutes. Mix in tomato paste and Worcestershire sauce, then sprinkle flour over the mixture and stir to incorporate. Add stock, thyme and peas and cook briefly until stock begins to thicken (if frozen peas are used, allow for the peas to begin to defrost). Remove from heat and set aside.
Sprinkle cheese over lamb mixture then top with prepared mashed potatoes. For a decorative finish, run a fork through the mashed potatoes to create swirls and ridges.
Bake for 20–25 minutes, until liquids begin to bubble around the edges and the top ridges of the potatoes begin to brown. Let cool 5 minutes before serving.