Cook lentils according to package directions using water/broth and set aside. Reserve some of the broth for extra liquid later on.
Place sweet potatoes in a pot of water until they are covered. Add salt. Bring to a boil over high heat. Then reduce to medium-high heat and cook for 15-20 minutes until soft. (Test by sticking fork in it and if it comes out easily they are ready)
Preheat oven to 425 F. If assembling casserole without baking and prepping this ahead of time, skip this step.
Once potatoes are cooked, drain and transfer to a large mixing bowl and mash until smooth then add coconut oil/grass fed butter and season with paprika and salt and pepper to taste then set aside.
Heat coconut oil in deep dish frying pan over low - medium heat and add onions, mushrooms and garlic and cook until just softened. If using ground turkey, add to pan and cook, breaking up the pieces throughout.
Stir in frozen peas, carrot, thyme and Worcestershire and season with salt and pepper. Fold in the lentils (shouldn't be super watery though!)
Transfer lentil and vegetable mixture to the 8x8 baking dish and spread evenly. Make sure there's enough liquid throughout. If not, add more broth as needed. Then top with mashed sweet potato and spread evenly over the mixture with a fork.
Bake in the oven for 10-15 minutes until potatoes start to turn golden brown. For maximum flavor, let sit before serving to allow everything to combine.*