Prep the pan: Line an 8x8-inch pan with parchment, leaving overhang on two sides for easy lifting.
Lightly grease the parchment so layers release cleanly.
Bottom chocolate layer: Melt 1 1/2 cups chocolate chips with 1 tablespoon oil in 20–30 second microwave bursts, stirring between each, until smooth. Spread evenly in the pan. Chill 10–15 minutes until set but not rock hard.
Make the nougat: In a small saucepan, melt the butter over medium-low heat.
Stir in sugar and milk; bring to a gentle simmer for 2 minutes, stirring often. Remove from heat. Whisk in marshmallow creme, peanut butter, vanilla, and a pinch of salt until smooth.
Layer the nougat: Pour the warm nougat over the chilled chocolate.
Spread gently to the edges. Chill 10–15 minutes to firm slightly.
Melt the caramel: In a microwave-safe bowl, combine caramels and heavy cream. Heat in 30-second bursts, stirring each time, until fully melted and pourable.
It should be thick but spreadable.
Add peanuts: Stir the roasted peanuts into the caramel. Immediately spread over the nougat in an even layer. If the nougat shifts, let it chill a few more minutes before adding the caramel.
Top chocolate layer: Melt the remaining 1 1/2 cups chocolate chips with the remaining 1 tablespoon oil.
Pour over the caramel peanut layer and smooth the top. Tap the pan gently to release air bubbles.
Chill and set: Refrigerate 45–60 minutes, just until firm enough to slice without cracking. If it gets too hard, let it sit at room temp for 10 minutes before cutting.
Slice cleanly: Lift the slab out using the parchment.
Warm a sharp knife under hot water, wipe dry, and cut into bars. Aim for 24 small bars or 16 larger ones.
Optional finish: Sprinkle a tiny pinch of flaky salt on top before the chocolate fully sets for a sweet-salty pop.