Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.

Cream together the softened butter and sugar in a large bowl until light and fluffy.

Add the egg and vanilla, mixing until fully incorporated.

In a separate bowl, whisk together the flour, baking powder, and salt. Slowly add the dry ingredients into the wet mixture. Mix until just combined.

In a small bowl, beat the cream cheese until smooth.

Gently fold the cream cheese and blueberry preserves into the dough. Swirl lightly with a spatula—don’t overmix! You want visible ribbons.

Use a cookie scoop or spoon to drop dough onto the baking sheet, spacing cookies about 2 inches apart.

Bake for 10–12 minutes, or until the edges are lightly golden.

Let the cookies cool on the pan for 5 minutes, then transfer to a wire rack.