8 Tablespoons Unsalted Butter, diced
1/4 cup Crunchy Peanut Butter
3/4 cup Dark Brown Sugar
1/4 cup Demerara Sugar + extra for rolling
1/4 teaspoon Vanilla Powder or 1/2 teaspoon Vanilla Extract
3/4 cup Flour
1/4 cup Cornstarch
1/4 teaspoon Kosher Sea Salt
1 egg beaten + Demerara Sugar, Optional
Using a stand mixer fitted with the paddle attachment or an electric hand mixer, beat the butter, peanut butter, both sugars and vanilla on medium-high until the mixture is light and fluffy, approximately 6 minutes.
In a separate bowl, whisk together flour, corn starch and salt.
Using a spatula, scrape down the sides of the bowl and, with the mixer on low, slowly add the flour mixture until combined.
Gather dough and place onto a long piece of waxed paper.
Shape dough into a rough 2" diameter log, then roll in waxed paper to smooth compact log shape. It does not need to be perfect, just as uniform as possible with the ends tight.
Unwrap the dough and roll in additional Demerara Sugar for extra texture and sweetness on the cookie edges.
Rewrap the dough log in the waxed paper.
Chill wrapped dough until totally firm, about 2 hours.
Pre-heat the oven to 350 degrees.
Using a serrated knife, carefully slice each log into 32 rounds.
Place onto baking parchment lined baking sheets about 1/2-1" apart.
Bake until the edges just begin to brown, approximately 12 to 15 minutes.
Transfer to cool before storing.
The cookie dough can be made ahead and stored, tightly wrapped in plastic, up to 1 week in the refrigerator, or 1 month in the freezer. Cookies can be baked and stored in plastic wrap or an airtight container for 5 days.
Makes 32 cookies.