In a large mixing bowl combine the peanut butter, unsalted butter, granulated sugar, light brown sugar, and salt. Whip until creamy – this should take a few minutes. Scrape down the edges of the bowl.
Add egg and vanilla and mix until combined.
Slowly add flour and baking soda, mix until just combined.
Using a cookie scoop or two teaspoons, scoop the dough into 1-inch balls. Coat in a thin layer of sugar. Place on the baking sheet about 2 inches apart from each other.
Bake for 8 to 10 minutes or until the bottom’s edges are just turning brown. Push a chocolate kiss into the center of each cookie (flat side of the kiss down). The cookies will mold shape and crack a little during this process. This must be done while the cookies are hot!
Let the cookies cool on the baking tray until set before moving them to a cooling rack.