Preheat oven to 350°F.
In a large bowl combine the peanut butter, coconut sugar, salt and vanilla extract together.
Add the egg and mix thoroughly to incorporate it (ensuring there are no clots or blobs of egg visible, alternatively you can whisk the egg in a separate bowl before adding it to the dough).
Add your finely ground blanched almond flour and baking powder and combine to form a firm dough.
Roll your dough into balls or scoop your dough by the tablespoonful onto a baking tray lined with parchment paper into 12-14 portions, and, using the tips of your fingers, make an indent in the middle of each cookie dough and work outwards to create an indent or "thumbprint".
Option 1: Fill each of the cookie indents with a spoonful of jam being sure to not overfill them.
Bake in your preheated oven for 10-12 minutes. Remove from oven and let cool. Note that the cookies will be soft when removed from the oven, they will harden as they cool.
Option 2: After baking and cooling slightly, fill each indent with a spoonful of jam.
Enjoy by themselves or with a cold glass of your favorite milk! Store any leftovers in an airtight container in your fridge for up to a week. If left unfilled, you can freeze your cookies for up to 3 months.