Line a small baking sheet with parchment paper. In a small bowl, combine the cold cream cheese, granulated sugar, and vanilla extract. Using an electric mixer on medium-high speed, beat until the mixture is fluffy and the sugar has dissolved, about 2 minutes. Using a teaspoon, scoop the cheesecake filling into 18 portions (about 2 teaspoons each) onto the prepared baking sheet. Gently flatten each scoop with the back of a spoon to form thick discs rather than rounded balls. Place the baking sheet in the freezer and freeze until completely solid.

In a medium saucepan, combine the diced strawberries and granulated sugar. Cook over medium heat for about 45 minutes, stirring frequently and smashing the strawberries with a wooden spoon halfway through. Toward the end of cooking, stir continuously to prevent sticking as the jam thickens. The jam should reduce to a thick consistency, about 1/3 cup (80 ml). Remove from heat and transfer to the refrigerator to chill while preparing the cookie dough.

Preheat the oven to 350°F (175°C) and line two baking sheets with parchment paper. In a medium bowl, whisk together the all-purpose flour, baking powder, baking soda, and salt. Set aside. In a large mixing bowl, cream the softened butter and granulated sugar using an electric hand mixer or stand mixer fitted with a paddle attachment on high speed until light and fluffy, about 2 minutes. Add the egg and vanilla extract and continue mixing on medium speed until pale and very fluffy, about 1-2 minutes. Gradually add the dry ingredients and mix on low speed just until combined.

Transfer about three-quarters of the dough to one side of the bowl and flatten the remaining quarter at the bottom. Spoon a quarter of the chilled strawberry jam onto the flattened dough. Layer another quarter of the dough on top of the jam and spoon another quarter of the jam over it. Repeat this layering process one more time. Using a rubber spatula, “cut” the dough into quarters and gently fold each section just until the jam is partially incorporated, leaving pockets of jam visible throughout the dough.

Use a 2-tablespoon cookie scoop to portion the dough into 18 even portions. Slightly flatten each dough ball, then place one frozen cheesecake disc in the center. Fold the cookie dough around the cheesecake filling, ensuring it is fully enclosed, and shape each into a slightly flattened disc. Roll each cookie dough disc in granulated sugar to coat evenly.

Keep the cheesecake discs frozen until ready to assemble each batch. Place 6 cookies at a time onto the prepared baking sheets, spacing them evenly. Bake for 11-12 minutes or until the edges are set and the cookies have a crackly top. Right after baking, use a large circular cookie cutter to gently shape the cookies into perfect rounds if desired. Allow the cookies to cool on the baking sheet for about 10 minutes, then transfer them to a wire rack to cool completely before serving.