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

Cream together softened butter, granulated sugar, and brown sugar until light and fluffy, about 2-3 minutes.

Add eggs and vanilla extract to creamed mixture and mix until fully combined.

In a separate bowl, whisk together flour, baking powder, and salt. Gradually mix into wet ingredients without over-mixing.

Fold in blueberries and blueberry jam carefully to keep blueberries intact.

Chill the dough in the refrigerator for at least 30 minutes.

Scoop dough onto prepared baking sheet, spacing them about 2 inches apart.

Bake for 15 minutes, or until edges are lightly golden and centers are set.

Cool cookies on the baking sheet for 5 minutes before transferring to a wire rack.

Store in an airtight container at room temperature for up to 3-5 days.