Preheat oven to 450F. Place sweet potatoes on a baking sheet, bake for 45-60 minutes or until fully cooked and fork tender. Allow to cool the peel the skin off.
Peel the skin off then place the sweet potato flesh in a large bowl and mash well.
Mix the heavy cream, sugar or honey, eggs, cinnamon, salt and vanilla in with the sweet potato until well combined. Place in a baking dish (14.5x 11 x 2) or a smaller baking dish for a thicker casserole. Note: Mixture does not need to be smooth, some lumps are ok.
In a small bowl mix the flour, brown sugar and cinnamon, then mix in the melted butter and sprinkle the mixture all over the sweet potato. Garnish with whole or chopped pecans.
Bake at 350F until golden brown , for 35-40 minutes.