In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy.
Add the vanilla extract and mix until well combined.
Gradually add the flour and salt to the butter mixture, mixing until a dough forms. Be careful not to overmix.
Once the dough comes together, shape it into a ball and flatten it into a disc. Wrap the dough in plastic wrap and refrigerate for at least 30 minutes, or until firm.
Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
On a lightly floured surface, roll out the chilled dough to a thickness of about 1/4 inch.
Use heart-shaped cookie cutters to cut out cookies from the dough. Place the cookies on the prepared baking sheet, spacing them about 1 inch apart.
Gather any scraps of dough, reroll them, and cut out more cookies until all the dough is used.
If desired, use a toothpick or fork to create decorative patterns on the cookies.
Bake the cookies in the preheated oven for 12-15 minutes, or until the edges are lightly golden.
Remove the cookies from the oven and let them cool on the baking sheet for a few minutes before transferring them to a wire rack to cool completely.