In a stand mixer or mixing bowl, cream the butter until its smooth and fluffy.
Mix in the powdered sugar and vanilla. Cream until smooth.
In another bowl, whisk together the flour and salt. Add half of the flour-salt to the butter and mix together. Add the remaining flour-salt and mix together until dough forms.
Place a piece of plastic wrap or parchment paper onto the counter. Transfer the dough onto the counter. Wrap the plastic wrap/parchment paper around the dough and flatten into rectangular shape, about 1/2-inch thick. Refrigerate for at least 2 hours.
Preheat the oven to 300 F. Add a silicone baking mat to baking sheet.
Remove the chilled dough from the fridge. Unwrap and place the dough onto the prepared baking sheet.
Bake in the preheated oven for 45 to 50 minutes.
Remove and let cool. Slice into square or rectangular pieces. Enjoy these Ted Lasso cookies!