Add strawberries, sugar, and lemon juice to a saucepan. Cook over medium heat, stirring often, until thick and jam-like (10–12 minutes). Remove from heat and cool completely.

In a bowl, whisk together flour, baking powder, and salt. Set aside.

In a large bowl, beat butter and cream cheese until smooth and creamy.

Mix in granulated sugar and brown sugar until fluffy. Add egg and vanilla extract, beating until combined.

Gradually add dry ingredients to the wet mixture. Mix just until a soft dough forms.

Cover and refrigerate dough for 30 minutes to prevent spreading.

Scoop dough balls onto a lined baking sheet. Press a small indentation in the center and fill with cooled strawberry jam.

Bake at 350°F (175°C) for 14–16 minutes, until edges are set and centers look slightly soft.

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