12tablespoonssalted butter, or use unsalted and add and extra ½ scant tsp salt(170 grams)
¼cuppeanut butter,sweetened (like Jif)(64 grams)
1cupdark brown sugar, tightly packed(220 grams)
¾teaspoonvanilla
1 ½cupsall-purpose flour(195 grams)
¼teaspoon salt
1teaspoonbaking soda
2cupsquick cooking (not instant)(140 grams)
1largeegg
Fudge Filling
14ozsweetened condensed milk
2tablespoonsbutter(28 grams)
2cupssemisweet chocolate chips
1teaspoonvanilla
Instructions
Preheat oven to 350 degrees F. Line a 15x10 inch rimmed metal pan (jelly roll) with parchment paper or non-stick foil.
In large bowl, combine softened butter, peanut butter, brown sugar and vanilla. Beat by hand or on low speed of a mixer just until blended. Mix together the flour, salt, baking soda and oats. Add to batter and stir until blended.
Set aside about 1 ⅓ cups (260 grams) of the peanut butter mixture.
Stir egg into remaining peanut butter mixture in bowl. Scrape into the greased pan and use dampened fingers to press into a thin layer across the bottom of the pan.
Set the jelly roll pan on a slightly smaller rimmed pan so that it's resting on the smaller pans rims, then bake for 15 minutes. If you want, you can set it directly on the rack. Having it float on a smaller pan gives you a slightly softer crust. Let cool for about a half hour.
Heat the condensed milk, butter and chocolate chips in a small saucepan set over medium heat stirring until chips are melted and smooth. Remove from heat and stir in vanilla. Pour over the crust.
Break up reserved oatmeal mixture and scatter lumps (jumbles) over the top of the fudge. Note: If you happen to have some peanut butter chips lying around, they are not a bad addition.
Bake 25 minutes (again, resting on rim of smaller pan) or until peanut butter oat topping is golden brown. Set on a cooling rack and cool completely. When bars are absolutely, completely cool, go ahead and cut. Store leftovers covered at room temperature or freeze.
Notes
Letting the crust cool before pouring on the fudge topping helps prevent it from overbaking during the second bake.