Heat a glug of oil in a large casserole or deep frying pan and gently fry the onion and spring onions for 5 minutes until softened. Turn up the heat to medium, add the rice and garlic, and fry for 1 minute until the rice is coated in the oil and turning translucent.
Pour in the wine, stirring all the time, and let it almost fully reduce. Turn down the heat to low-medium and slowly add the stock, a ladle at a time, stirring regularly, only adding more once the last ladleful is absorbed. Season.
For the green sauce, put the spinach, peas, olive oil and 100ml of water in a blender or food processor. Blitz to a smooth sauce.
When you have added all the stock and the rice is nearly cooked (this will take about 25-30 minutes), stir in the green sauce. Keep stirring the risotto for a further 10 minutes, then stir in the peas, parmesan, lemon and cream. Season and simmer for 5 minutes until the peas are cooked and the rice is tender.
Mix together all of the crab salsa ingredients. To serve, spoon the risotto into bowls and top with crab salsa and a drizzle of olive oil. Serve with lemon wedges and parmesan.