01 - Preheat oven to 350°F. Lightly grease a 24-cup mini muffin tin with cooking spray or butter.
02 - In a medium bowl, whisk together the flour, baking soda, and salt until well combined. Set aside.
03 - In a large bowl, beat the softened butter and granulated sugar with an electric mixer on medium speed until light and fluffy, approximately 2 minutes.
04 - Add the egg and vanilla extract to the butter mixture. Beat until fully incorporated and smooth.
05 - Gradually add the dry ingredients to the wet mixture, mixing on low speed just until the flour disappears. Do not overmix.
06 - Scoop approximately 1 tablespoon of dough into each muffin cup. Press gently with fingers or the back of a spoon to form a cup shape, pushing the dough up the sides to create a well.
07 - Bake for 10 to 12 minutes until the edges are lightly golden. The centers should still be slightly soft.
08 - Remove from oven and immediately press the center of each cookie with the back of a spoon while warm to deepen the cup shape. Cool in the tin for 10 minutes, then transfer to a wire rack to cool completely.
09 - In a chilled bowl, whip the heavy cream, powdered sugar, and vanilla extract with an electric mixer on high speed until stiff peaks form.
10 - Fill each cooled cookie cup with the whipped cream filling using a spoon or piping bag. Top immediately with fresh berries, sprinkles, or mini chocolate chips as desired.