Place a paella pan (or wide frying pan) over medium heat and add the olive oil. When the oil is hot, add the squid rings and saute for 30 seconds. Remove from pan and set aside for now.
Add the onion and bell pepper to the pan (adding more olive oil if needed), and saute for 4-5 minutes or until the onion is soft and translucent. Add the garlic, paprika, cumin, and saffron and saute for another minute until aromatic.
Stir in the tomato paste and cook for another 2 minutes. Pour in the rice, stirring to coat in the tomato and spice mix. Add the wine and let it simmer for 5 minutes or until the wine has almost completely evaporated.
Add the stock and squid ink to the pan and stir to combine. Season with salt. Bring to the boil and immediately reduce to a gentle simmer. Leave for 15 minutes until the stock has reduced and the rice is almost cooked. Resist the urge to stir! Leave the rice as is so that the socarrat has time to develop on the bottom of the pan.
Add the prawns on top of the rice and cook for another 4-6 minutes until fully cooked. Add back the squid.
Take off of the heat and leave to settle for about 10 minutes. Serve straight out of the pan and garnish with lemon wedges.