Preparation Steps:

• Step 1: Preheat your oven to 350°F (175°C) to give your cookies a perfect golden finish.
• Step 2: In a medium bowl, whisk together the all-purpose flour, fine sea salt, baking soda, and baking powder. Set this aside.
• Step 3: In a large mixing bowl, beat the unsalted butter, light brown sugar, and granulated sugar together until light and fluffy (about 2-3 minutes).
• Step 4: Add the egg, creamy peanut butter, and vanilla extract to the butter-sugar mixture and beat until fully combined and smooth.
• Step 5: Gradually add the dry ingredient mixture to the wet ingredients, mixing until just combined.
• Step 6: Scoop out tablespoon-sized portions of dough and roll them into balls. Roll each ball in granulated sugar for a sweet finish, then place on a cookie sheet lined with a silicone mat or parchment paper.
• Step 7: Using your thumb (or the back of a spoon), gently press down in the center of each ball to create a well for the jam.
• Step 8: Fill each thumbprint with your favorite jam.
• Step 9: Bake the cookies in the preheated oven for about 12-15 minutes, or until the edges are lightly golden.
• Step 10: Allow the cookies to cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely.