Preheat your oven to 350°F and line a small baking sheet with parchment paper.
In a small mixing bowl, combine the almond flour, egg white, baking soda, monk fruit sweetener, sea salt, and half of the vanilla extract.
Stir the mixture until a thick dough forms, then divide it into four equal portions.
Place the dough portions on the baking sheet and flatten them into small, even discs.
Bake for 8 to 10 minutes until the edges are lightly golden and the centers are set.
Remove the cookies from the oven and allow them to cool completely on a wire rack.
In a separate bowl, whisk together the Greek yogurt, maple syrup, and the remaining vanilla extract until smooth.
Spread the yogurt mixture onto the flat side of two cookies, then top with the remaining two cookies to create sandwiches.
Place the sandwiches in the freezer for 20 to 30 minutes to allow the filling to firm up before serving.