Pour fish stock into the pot and add cinnamon quill and star anise. Bring heat up to a very gentle simmer to allow spices to infuse the stock.
Meanwhile heat olive oil in a frying pan over medium heat, add the fennel seeds and half the garlic and cook for one minute.
Add sliced fennel to the fry pan and cook for 3 - 4 minutes until fennel is softened.
Add clams and mussels to the pan and stir fry for 1 minute. Then add vermouth and continue cooking until mussels and clams have opened about 3 - 4 minutes (if your clams and mussels are taking a little longer to open, cover the pan with a lid until they do).
Once clams and mussels have opened remove fennel, mussels and clams from the pan to a plate and set aside.
In the same pan add butter and the rest of the garlic and cook for 1 minute until the garlic softens. Then add the rice and stir with a wooden spoon, ensuring each grain is coated. Toast rice like this for two minutes then add the cherry tomatoes.
Now its time to add the fish stock, take a ladle of the hot stock and transfer to the rice mixture, stir slowly until the stock has absorbed into the rice. Continue to do this ladle by ladle until the stock is all used up. (don't transfer the cinnamon or star anise to the pan, discard them after all the stock is used).
Once you have added the last ladle of stock, add the prawns and cook for 1 minute, then add the calamari and cook for another minute, lastly add back the fennel, clams and mussels and stir to warm through.
Serve risotto on a large platter, scattered with fresh basil leaves and reserved fennel fronds.
Enjoy immediately.