Preheat oven to 350°F. CRUST: Toast the pecans about 10min in a toaster oven (shaking every 2 minutes or so) or in a small skillet over medium heat (stirring frequently). Remove from heat and blend in a food processor or mixer until texture resembles a coarse meal. Combine the pecan meal, coconut flour, sugar, and salt in a mixer with paddle or in a food processor. Add the butter and pulse until mixture resembles bread crumbs. Add three eggs and pulse until dough forms. Roll the dough between two pieces of parchment or baking paper, remove the top paper, invert over pie pan and remove top paper. Press thumb around perimeter to make a pretty pattern all around. Set aside in fridge. FILLING: Beat or whisk all ingredients until well combined. Pour into the prepared crust. Bake 45min or until a toothpick comes out clean (might be up to 15 minutes longer). Cool and serve with whipped cream.