Pre-heat the oven to 356°F. Pierce the datterini tomatoes with a small sharp knife to allow the juices to run out during the cooking and intensify the flavour of the sauce. Place in a bowl and add vinegar, extra virgin olive oil, a pinch of salt and marjoram leaves. Toss together to coat the tomatoes and place in a baking tray. Roast in the middle shelf of the oven until soft and tender.
Remove from the oven and spoon the tomatoes and the cooking juices into a shallow saucepan. Place over a medium heat and add the garlic cloves, olives and dried chili. Cook gently for 5 mins just to allow the flavours to marry. Taste and adjust seasoning if necessary. Finely chop the leaves from the sprigs of mint, stir through and bring a large pot of salted water to a boil, then cook tortelloni following package instructions.
Drain delicately with a skimmer and place tortelloni in the saucepan, adding 2 tbsp of pasta cooking liquid.