Preheat oven to 325ºF and grease three 8-inch round cake pans well. Line the bottom of the pans with circles of parchment and grease the parchment.

In a medium bowl, whisk together the almond flour, sweetener, cocoa powder, protein powder, baking powder, and salt.

Stir in the sour cream, eggs, and vanilla. Stir in the water one tablespoon at a time until the batter is thick but pourable.

Divide batter evenly among prepared cake pans and bake 15 to 20 minutes, or until just firm to the touch. Remove and let cool completely in the pans.

In a large bowl, beat the peanut butter, cream cheese, and butter together until very smooth, about 2 minutes. Beat in the sweetener and vanilla extract.

In a separate bowl, whip the cream until it holds stiff peaks. Fold into the peanut butter mixture until no streaks remain.

Place one layer of cake on a serving platter and spread with about one quarter of the frosting. Top with another layer of cake and another quarter of the frosting.

Add the remaining layer of cake and spread the top and sides with the remaining frosting. Refrigerate for one hour to firm up.

In a small saucepan over medium heat, bring the cream to a simmer. Remove from heat and add the chopped chocolate. Let sit a few minutes to melt.

Add the sweeteners and whisk to combine. Let cool a few minutes to thicken, and then slowly drizzle over the top of the cake along the edges, letting it drip down the sides.

Smooth the remaining glaze over the top of the cake. Top with keto peanut butter cups and sprinkles, if desired.