Preheat the oven to 325ºF and line a baking sheet with a silicone baking mat or parchment paper.

In a large bowl, beat the softened butter until soft and creamy, then beat in the powdered Swerve sweetener. Add the egg yolk and vanilla extract and beat until well combined.

All at once, add the almond flour, baking powder, and salt. Beat until the dough comes together.

Divide the dough into 14 equal portions and roll into balls. Place the balls several inches apart on a large baking sheet lined with parchment or silicone. Press down to about 3/4 inch thick with the palm of your hand. Take a rounded tablespoon or other rounded implement and press a large indent into each cookie.

Bake 18 to 20 minutes at 325ºF, until just beginning to brown around the edges. They will still be very soft and a little puffy. Remove and gently reform the wells while the cookies are still hot. Let cool completely on the pan (the cookies will firm up as they cool).

Once cool, make the keto caramel sauce according to the directions, then spoon into the wells of the cookies. Refrigerate to help set the caramel, about 20 minutes.

In a medium saucepan over medium heat, whisk the heavy whipping cream and allulose together and bring to just a simmer. Remove from heat and add the chopped sugar-free dark chocolate. Let sit 5 minutes to melt, then whisk until smooth.

Spoon the chocolate over the tops of the cookies and spread lightly over the caramel filling. Sprinkle with a little flaked sea salt, if desired.