In a large mixing bowl, use a hand mixer on medium speed to combine butter and sugar.
Add the flour and salt and combine with your hand mixer on medium speed.
Add the egg yolk and lime juice and combine with your hand mixer on low (see tip below on how to separate egg yolks).
Fold in the lime zest.
Use a large cookie scoop or wet hands to form your dough into 8 round cookies and place them on a lined baking sheet, leaving at least an inch of space in between each cookie.
Place the cookie sheet with your cookie dough in the freezer to set for 30 minutes.
Preheat the oven to 325°F.
Bake cookies for 14-16 minutes, until the outer edges just start to brown.
Allow the cookies to cool completely before adding glaze.
Add tequila and 1 teaspoon of lime juice to a large mixing bowl.
With your hand mixer on low, add ¼ cup powdered sugar. Keep your mixer on and continue to add more powdered sugar, about 1 tablespoon at a time, checking the consistency as you go. You will know you've added the right amount of sugar when the glaze is just thick enough to slowly drip off of a spoon.
Once your cookies have cooled, drizzle the glaze on top and add some more lime zest for a fun and fragrant finish!
