Wash and cube potatoes. Place potatoes in a large pot of water and bring to a boil. Cook until the potatoes are soft, about 10 minutes and then drain.
Lightly coat a non-stick pan with cooking spray or oil and heat over medium-high heat. Add onions and cook for about 5 minutes, until browned. Add ground turkey and cook until brown.
Add lentils, Worcestershire sauce and tomato paste to the ground turkey.
Pour ground turkey mixture into an 8×8 casserole dish and spread evenly across the bottom. Layer peas and carrots on top of turkey mixture.
Add margarine and milk to the drained boiled potatoes. Mash with a potato masher or a hand blender. Layer mashed potatoes overtop peas and carrots and spread evenly.
Place in the oven on the lower rack and broil for 5 to 10 minutes until potatoes begin to brown. Remove from the oven and serve.
6 servings