Place 12 half-teaspoon portions of preserves onto a parchment-lined tray and freeze for 30 minutes until firm.

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

In a large bowl, cream together the softened butter, peanut butter, granulated sugar, and brown sugar until light and fluffy.

Mix in the egg and vanilla extract until well combined.

Whisk together the flour, baking soda, and salt in a separate bowl, then gradually incorporate into the wet ingredients.

Divide the dough into 12 equal portions (about 1.5 tablespoons each).

Flatten each dough portion, place a frozen preserves dollop in the center, and fold the dough to seal it completely inside.

Arrange the dough balls 2 inches apart on the prepared baking sheet.

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

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