Do ahead or before. Wash, pat dry and pierce 3 large orange sweet potatoes. Place on papertowel and microwave for approximately 15 minutes (quick method). You may prefer to boil or bake which takes much longer. Allow to cool to touch and peel potatoes. (*Tip - If you are not cooking the casserole sameday, cover and refrigerate your sweet potato mash until ready to use. Heat up in microwave so the temperature is warm and not cold before adding other ingredients to bake).
Preheat oven to 400 degrees F. Spray a large, deep-dish casserole baking dish with non-stick coating and gently wipe any excess out with paper towel. Set aside.
Place potatoes in a large mixing bowl and mash with regular potato masher until smooth consistency. Add sugars, well beaten eggs, flour, cinnamon and cloves. Stir well. Add cream gradually stirring until thoroughly mixed. Add melted butter and stir until smooth. Add vanilla flavoring and stir well again. Pour or scoop mixture into deep-dish casserole baking dish.
Topping - using a medium sized mixing bowl combine flour, coconut, chopped pecans and brown sugar. Mix lightly with hands. Add room temperature butter or margarine to this and mix gently. Crumble this topping over the sweet potato mixture. Bake for 45 minutes on 400 degrees F.
Optional: Remove casserole from oven and lightly sprinkle a cup of mini marshmallows on top. Return to oven for last 15 minutes keeping close eye on. When melting and puffy - times up! Remove and allow to set for 15 minutes before serving. (Great for leftovers and reheating)