Preheat oven to 350 ° F. Add 2 cups nuts to food processor and use the pulse button to get them ground to a consistency you like. Think of a grainy meal. (See photo above or video for what it should look like)
Microwave the butter a couple seconds to melt. In a bowl, add ground nuts, butter and salt. (You can add some sugar substitute at this time also, but it is optional). The nuts should stick together if you make them into a ball with your hand.
Use a little butter to grease the bottom and sides of a 9” pie shell. Gather the nut mixture into a large ball and place in the middle of the greased pie shell. Starting from the middle and working outward, pat and press the nut mixture around the bottom and up the sides of the pie shell using your fingers and knuckles. Bake in the preheated oven for 15-20 minutes until lightly browned.
While the crust is cooking make the filling. Add the cup of heavy cream to a stand mixer using the whisk attachment. Beat at a slow speed until it forms stiff peaks form. Start slow and increase speed as it thickens or it will splatter all over. See above photo or the video if you want to see what stiff peaks look like. Remove whipped cream to a bowl and rinse out or wipe the inside of the stand mixer bowl.
In the stand mixer using the paddle attachment this time, add the cream cheese and powdered sugar (*note: for DIY powdered sugar, pour granulated sugar or sugar substitute into a blender and briefly to a powdered state). Beat the cream cheese and powdered sugar until creamy (about 2 minutes). When creamy smooth, add the rest of the ingredients (excepting the garnish) and beat until thoroughly combined, scraping down the sides to combine.
Remove the stand mixer bowl from the stand and gently fold the whipped cream into the cream cheese mixture still in the stand mixer bowl. Do not overstir, but fold it in until combined. If the nut crust is cool, spread the entire filling into the crust with a spatula, swirling it a bit for effect :). Cover with plastic wrap and chill in the refrigerator for at least 4 hours or overnight. When thoroughly chilled, thinly slice the oranges and lemons and arrange on the pie. Serve and enjoy! Keep leftovers refrigerated.