Preheat your oven to 375°F (190°C).
In a large bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.
Beat in the egg and vanilla extract.
In a separate bowl, whisk together the flour, baking soda, and salt.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Do not overmix.
Stir in the chocolate chips.
Chill the dough for at least 30 minutes.
Roll out the dough and use a heart-shaped cookie cutter to cut out cookies.
Place the cookies on a baking sheet and bake for 8-10 minutes, or until the edges are golden brown.
Let the cookies cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.