Put the rice in a large saucepan of cold water. Bring to the boil, then simmer for 5 mins and drain.
Meanwhile, put the oil in a large frying pan or shallow casserole with a lid, set over a low heat. Working in batches, fry the chorizo, turning occasionally, until brown and crisp at the edges. Remove to a plate.
Add the chopped onion, peppers and aubergines to the pan with the lemon juice. Fry for 10 mins, stirring, to soften the veg. Stir in the garlic for 30 secs, followed by the drained rice, tomatoes and stock. Bring to a simmer, then cover and cook for 10 mins or until the rice is just tender.
Stir the lemon zest, chopped parsley and some seasoning through the rice, fluffing up as you go. Top with the crispy chorizo slices and the parsley leaves and serve with lemon wedges for squeezing over.