Combine pecans and almond flour in a food processor and blend until fine. Melt butter in a saucepan, then add nut mixture and stevia, and cook until slightly toasted. Grease the bottom of a 9" springform pan, spread the nut mixture evenly, then press into a firm layer. Bake at 400 for 5-10 minutes or until slightly golden.
Filling
Combine all ingredients except strawberries in the bowl of a mixer, and mix until well blended and smooth. If desired, slice strawberries and place around edge of the pan. Pour filing over crust and smooth into an even layer. Top with strawberries if desired.
Place cake in a preheated 400 degree oven, then reduce temperature to 250 and bake for 60-90 minutes or until the center has just set. Allow to cool completely before refrigerating. Serve with whipped cream.