Preheat the oven to 325°F (163°C). Line a baking sheet with parchment paper.
In a large bowl, cream the softened butter and granulated sugar together until light and fluffy using a hand mixer or stand mixer.
Add the salt and mix to combine.
Gradually add the all-purpose flour to the butter mixture, mixing on low speed until the dough just comes together. Do not overmix.
Turn the dough out onto a lightly floured surface and gently knead it a few times to bring it together.
Roll the dough out to about 1/4 inch thickness.
Use a cookie cutter or knife to cut the dough into desired shapes (e.g., rectangles or circles).
Place the cookies on the prepared baking sheet about 1 inch apart.
Optional: Use a fork to prick the tops of the cookies for a classic shortbread look.
Bake for 20-25 minutes, or until the edges are lightly golden.
Remove from the oven and allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.