Prepare your dough ahead of time

Fire up your Ooni Pizza Oven. Aim for 400˚C (750˚F) on the baking stone (use the Ooni infrared thermometer to accurately check the temperature).

Lightly dust your peel with flour or fine semolina then stretch out the dough to anywhere from 12 to 14 inches and lay it on your peel. 

Drizzle the pizza base with a little olive oil starting from the outside in, then sprinkle the dark chocolate evenly over the dough.

Slide the pizza off the peel and into the oven. Cook for 1 to 2 minutes, turning every 20 seconds or so. Remove the pizza when it’s around 75% done, the crust should be cooked, but paler than you’d normally expect from a finished pizza. 

Immediately top the pizza with marshmallows and return it to the oven to finish cooking for another 30 to 60 seconds, turning regularly. Remove once the marshmallows are toasted to your liking. 

Finish the cooked pizza with crushed graham crackers. Dust with powdered sugar to finish, slice, and serve right away.