Prep your pan. Line an 8x8-inch square baking pan with parchment paper, leaving some overhang for easy lifting.
Mix the peanut base. In a bowl, stir together peanut butter, almond flour, powdered sweetener, melted butter (or coconut oil), vanilla, and salt. The mixture should be thick but spreadable.
If it’s crumbly, add 1–2 teaspoons more melted fat.
Press and level. Scoop the peanut mixture into the lined pan. Press it firmly into an even layer using a spatula or the back of a spoon.
Chill briefly. Place the pan in the freezer for 10–15 minutes to set while you make the topping.
Make the chocolate topping. In a microwave-safe bowl or over a double boiler, melt the sugar-free chocolate chips with the heavy cream. Heat in short bursts, stirring until smooth and glossy.
Pour and smooth. Remove the pan from the freezer.
Pour the chocolate over the peanut layer and spread it evenly. Tap the pan lightly on the counter to settle the topping.
Add finishing touches. Sprinkle flaky sea salt or chopped peanuts on top, if you like.
Set fully. Refrigerate for 1–2 hours, or freeze for about 30–40 minutes, until the chocolate is firm and the bars hold their shape.
Slice cleanly. Lift the slab out by the parchment. Use a sharp knife warmed under hot water and wiped dry to cut into 16 squares.
Serve and store. Enjoy chilled for the best texture and clean slices.