Preheat oven to 325F and line a baking sheet with parchment or a silicone liner.
In a medium bowl, whisk together almond flour, coconut flour and baking powder.
In a large bowl, beat butter with sweetener until well combined and fluffy. Beat in egg yolk and almond extract. Beat in almond flour mixture until well incorporated.
Form dough into scant 1 inch balls and place two inches apart on prepared baking sheet. Press each ball down to about 1/2 inch high. Using your thumb, press an indentation into the center of each cookie.
Spoon about 1/2 teaspoon of jam into each and bake until just barely browning around the edges, 10 to 12 minutes. Cool on pan. The cookies will not seem set but will continue to firm up at they cool.
In a small bowl, whisk together sweetener, almond extract and water until a pourable consistency is achieved. Drizzle over cooled cookies.
Serves 12 (2 cookies per serving). Each serving has 4.98 g of carbs and 2.44 g of fiber. Total NET CARBS = 2.54 g.Food energy: 178kcal Saturated fatty acids: 5.69g Total fat: 16.00g Calories from fat: 143 Cholesterol: 35mg Carbohydrate: 4.98g Total dietary fiber: 2.44g Protein: 4.16g Sodium: 95mg