- Preheat the oven to 350 °F
- Roll the dough into the pan and prick it generously with the fork. Reserve cool.
- Brown onions in olive oil and butter over medium heat without staining. When the onions are translucent, salt, pepper and add a little cayenne pepper, then the balsamic vinegar. Mix well and reserve.
- Take the dough out of the fridge, work the mascarpone a little bit so that it is easy to spread, then spread it over the dough with the back of a table spoon. Season with salt and pepper and sprinkle with chopped chives. Cover with onions.
- Place in the oven and cook for 25 to 30 minutes.