Preheat the oven to 350°F. Line 2-3 baking sheets with parchment paper and set aside.
In a large microwave-safe bowl, melt the butter and peanut butter together (this takes about 45 seconds to 1 minute in my microwave). Stir until there is one homogenous melted butter-peanut butter mixture, then whisk in the Domino® Light Brown Sugar. My whisk of choice is actually a fork, but a normal whisk works too.
Whisk in egg and vanilla until mixture is well-combined. Add the baking soda and salt and whisk until fully incorporated.
Add the flour and stir with a fork or spatula until a fairly stiff dough is formed. You may need to put in some elbow grease with a spatula or your hands to get it to come together, but it will.
Scoop dough using a 1.5 teaspoon cookie scoop or two small spoons, then roll it between your palms to create a smooth, 1-inch dough ball. Place the granulated sugar in a bowl, then roll the cookie dough balls in the sugar until completely coated.
Space the cookie dough balls 2 inches apart on the cookie sheets. Bake, one sheet at a time on a center rack in the oven, for 8 minutes. Cookies will puff and be pale, and a few cracks may appear on the tops.
While cookies are baking, unwrap all of the chocolate kiss candies. When cookies come out of the oven, immediately press a chocolate kiss into the center of each cookie, so that the edges become crackled and the kiss is settled in the middle. Do not wait longer than a minute after the cookies come out of the oven to do this, or the cookies will already be too set and you won't get the same effect!
Place baked cookies in the refrigerator for 30 minutes to prevent chocolate kisses from melting (unless you like them that way!). Once chocolate is solid, cookies can be stored at room temperature in an airtight container for up to 5 days.