Preheat oven to 375 degrees F (190 degrees C). Line baking sheets with parchment paper.
All-Purpose Flour (1 3/4 cups)
Baking Powder (1 tsp)
Baking Soda (1/2 tsp)
Coarse Kosher Salt (1/2 tsp)
. Set aside.
Using an electric mixer, beat the
Powdered Confectioners Sugar (1/2 cup)
Dark Brown Sugar (1/2 cup)
Unsalted Butter (1/3 cup)
in a large bowl to blend.
Creamy Peanut Butter (1/2 cup)
and beat until creamy. Gradually beat in
Vegetable Oil (1/2 cup)
Pure Vanilla Extract (1/2 Tbsp)
Large Egg (1)
Add the dry ingredients; mix just until blended. Stir in the
Bittersweet Chocolate Chips (1 1/3 cups)
Drop cookie dough by level tablespoonfuls onto the prepared baking sheets, spacing about 1 1/2-inches apart.
Bake cookies until puffed and golden brown, about 10-12 minutes. Cool slightly, then transfer cookies to rack to cool completely.
To make the filling, place
Bittersweet Chocolate (2/3 cup)
Creamy Peanut Butter (1/4 cup)
Powdered Confectioners Sugar (2 Tbsp)
Coarse Kosher Salt (1/4 tsp)
in a medium bowl.
Whipping Cream (1/3 cup)
to boil in a small heavy saucepan. Pour the heated cream over the chocolate mixture; stir continuously until the mixture is melted and smooth.
Chill until the filling is thick and spreadable, about one hour.
Spread about 1 rounded tsp of the chocolate-peanut butter filling on the flat side of one cookie. Top with a second cookie, forming a sandwich. Repeat with remaining filling and cookies.