1 package chocolate cake mix (regular size)
2 large eggs, room temperature
1/2 cup canola oil
1 cup semisweet chocolate chips
1 cup creamy peanut butter
1/2 cup confectioners' sugar
Optional: Hot fudge ice cream topping, vanilla ice cream, whipped cream and melted creamy peanut butter
Preheat oven to 350°. In a large bowl, combine cake mix, eggs and oil until blended. Stir in chocolate chips. Press half the dough into a 10-in. cast-iron or other ovenproof skillet. Combine peanut butter and confectioners' sugar; spread over dough in skillet. Press remaining dough between sheets of parchment into a 10-in. circle; place over filling.
Bake until a toothpick inserted in center comes out with moist crumbs, 20-25 minutes. Serve warm, with optional ingredients as desired.