Heat half of the olive oil in a large heavy-based frying pan over medium heat. Cook chicken, stirring, for 2–3 minutes, or until golden. Remove from pan and set aside.
Return same pan to medium heat and add remaining oil. Cook onion and chorizo, stirring, for 5 minutes, or until chorizo is crisp. Add paprika and garlic; cook, stirring, for 1 minute. Add rice; stir to coat grains in oil.
Add the saffron liquid, stock, tomatoes and chicken to pan with 1/2 cup water; stir to combine. Bring to the boil, then reduce heat to low; cover and simmer for 15–20 minutes, or until rice is almost tender, adding a little water if it is becoming too dry.
Remove lid and place roasted capsicum, broccoli, peas and prawns on top of rice. Cover and cook for 5 minutes, or until prawns are cooked through. Mix through the black beans. Garnish paella with parsley and serve with lemon wedges.