Preheat the oven to 360 °F (180 °C). Grease an 8 or 9-inch round baking pan with some butter. Grease another, smaller baking pan as well. Using an electric mixer, mix together 5 eggs, 1 tbsp. psyllium husks, eryhtritol, and baking powder. Pour around 3/4 of the mixture into the round baking pan for the crust. Pour the rest into the smaller pan for the decoration strips. Bake for 10 minutes. A toothpick, inserted into the middle, must come out clean. While the two are cooling down, prepare the filling. When cooled down, keep the crust in the pan. Take the remaining 2 eggs and separate the whites from the yolks. In a medium bowl, using a hand electric mixer, mix together cream cheese, egg yolk, granulated erythritol, stevia extract, and vanilla. In a separate bowl, using an electric mixer, beat the egg whites. When they become fluffy, add in cream of tartar and powdered erythritol. Beat until stiff peaks form. Using a spatula, carefully fold the egg whites into the cream cheese and yolk mixture. You want this mixture to remain airy. Pour the filling on the cooled down crust. Using an electric mixer, blend together all four ingredients. Take the smaller patch of the "crust" and cut it into thin strips. Align the strips on top of the pie. Next, spoon the butter topping onto the pie. You don't have to be too delicate here because the topping will melt as soon as in the oven. I used decorating style solely for photo-taking purposes. ;) Shortcut: You can put the butter topping in a microwave for a few seconds, so it gets runnier. That way you can simply pour it over the top of the pie. That is what I will do the next time. Bake at 360 °F (180 °C) for another 20 minutes. Let it cool down, slice into 6 pieces, and enjoy. Keep leftover in the fridge for a couple of days. Pour a tbsp. of melted coconut oil over a slice to get in more healthy fats. Yum!