Clean the leek and peppers and cut into small pieces.
Roughly chop the walnuts.
Mix the mascarpone, sour cream and chopped chives. Season with salt, pepper and nutmeg.
Place the pizza dough on a baking sheet lined with baking paper and prebake for 4-8 minutes according to the instructions on the package. If air cushions / bubbles form, prick the dough with a fork.
Fry the leeks and peppers in the hot oil in a pan for 5 minutes, season and remove from the heat.
Take the pre-baked dough out of the oven, turn it over and brush with the sour cream mix.
Spread the vegetables, nuts and cheese on top. Bake for another 8 minutes at 200 degrees.