Peel and chop the onion and add to a large pan with the olive oil. Cook over a medium heat for about 5 minutes, until softened.
Pour 500ml water and the pesto into the pan and stir well; bring to the boil.
Tip in the gnocchi and the chopped asparagus; add a little more water if the gnocchi isn’t quite covered.
Add the peas and courgette (I shaved mine lengthways with a potato peeler) and simmer for 5 minutes, until the gnocchi is soft. Season if necessary with salt and black pepper.