Nutrition: Per serving (6)
Heat the oil in a large lidded pan over a medium-low heat and fry the onions with a pinch of salt for 8-10 mins until beginning to soften, then stir in the peppers and cook for 5 mins more. Stir in the garlic and cook for 1 min before adding the pesto. Mix everything together and cook for a couple of minutes.
Pour in the stock, then add the rosemary or thyme, followed by the pasta. Stir everything together, bring to a simmer, put the lid on and cook for 12-14 mins until the pasta is almost cooked. Add a splash more water if necessary.
Stir in the spinach or frozen peas and cook for 2 mins, or until the spinach is wilted. Spoon in the mascarpone, crème fraiche or soured cream, then mix it in. Squeeze over the lemon, if using, then serve with grated Italian hard cheese scattered over, if you like.
