Preheat oven to 375°F (190°C). Line baking sheets with parchment paper.

Make the caramel filling: In a saucepan, combine sweetened condensed milk, butter, brown sugar, and heavy cream. Simmer, stirring constantly, until smooth. Cool completely.

Make the cookie dough: Cream together butter and sugar until light and fluffy. Beat in eggs, then vanilla. In a separate bowl, whisk flour, baking soda, and salt. Gradually add dry ingredients to wet ingredients, mixing until just combined.

Roll dough into 1-inch balls. Place a teaspoon of cooled caramel filling in the center of each ball. Gently enclose the filling.

Place cookie balls onto prepared baking sheets, leaving 2 inches between each. Bake for 10-12 minutes, or until edges are golden brown.

Let cookies cool on baking sheets for a few minutes before transferring to a wire rack to cool completely.

Make the cheesecake filling (optional): Beat together cream cheese, sugar, and vanilla until smooth. Frost cooled cookies with a dollop of cheesecake filling.