1. In one large cast iron skillet or a few small cast iron skillets like I did here, press in a thin even layer of peanut butter cookie dough. Place tagalongs in an even layer on top of the cookie dough, and then spread a thin even layer of brownie batter over the top, until all cookies are just covered. Don't fill to the top of the skillet, as it will expand as it cooks.
2. Bake in a preheated 350°F oven for 30 minutes if using small skillets, and up to approximately 45 minutes if one large skillet is used.
3. Let cool for 10-15 minutes, then top with a ridiculous amount of vanilla ice cream, hot fudge, and peanut butter dessert sauce. Garnish with extra Tagalongs, if available. Give everyone a spoon and devour.

for the Peanut Butter Chocolate Chip Cookie layer

1. In a small mixing bowl, combine flour, baking soda, and salt.
2. In your stand mixer or in a medium mixing bowl fitted with a hand mixer, cream together the butter, brown sugar, and granulated sugar on medium speed until light and fluffy, scraping down sides as needed. Add peanut butter and mix to until fully incorporated. Add egg + extra egg yolk and vanilla, and mix until fully combined. Slowly add flour mixture, scraping sides as needed, until just incorporated. Do not over-mix. Stir in chocolate chips. If making ahead of time, cover cookie dough tightly with plastic wrap and refrigerate. Leftover cookie dough not used in this recipe can be refrigerated up to 5 days or tightly wrapped and frozen for a few months.