Mix the butter and brown sugar together very well. Add the egg and vanilla and mix again. 

In another bowl, stir together the flour, salt and baking powder. 

Add the flour mixture to the butter mixture and stir just until combined. 

Refrigerate dough for 30 minutes.

Preheat oven to 350 degrees.

Scoop out a spoonful of dough, roll it into a ball and then roll in the granulated sugar.

Place the dough onto a parchment paper lined cookie sheet and press on the cookie with the tines of a fork.

Bake for 10-12 minutes.

Once the cookies are cool, share them with your family and friends!