1 1/2 teaspoon vanilla bean paste or extract (Note, vanilla bean paste will speckle your cookies with little black dots, which I personally find charming.)
Preheat oven to 400° F.
Sift together flour and salt; set aside.
Cream together butter and powdered sugar using electric mixer of your choice at medium speed. (I like to sift my powdered sugar first to get the lumps out.)
Reduce speed to low and blend in egg yolks and vanilla extract.
Scrape down sides of the bowl, if needed and add about half the flour mixture. Start mixer at low speed to prevent covering your kitchen in a cloud of flour. When that’s partially incorporated, add remaining flour and repeat. Increase speed a bit and blend until all flour is incorporated and dough begins to pull away from sides of the bowl.
Fill your cookie press with dough and spritz cookies about an inch or so apart onto a cool, ungreased cookie sheet. (If your kitchen is exceptionally warm, you might want to pop your cookie sheet in the freezer for a few minutes. If you have room, that is. I almost never do.)
Bake for 6 to 8 minutes. To ensure even baking, rotate pan halfway through cook time. Err on the side of underdone as brown edges detract from the prettiness. Just saying.
Let the cookies set on baking pan for a couple of minutes then transfer to cooling rack.