In a large, deep-sided frying pan, fry the shallots in a little oil for 5-10 minutes until soft but not coloured. Add the wine and cook for a couple more minutes until it has mostly evaporated.
Add the garlic, smoked paprika, chilli flakes, fennel seeds and orzo. Fry the orzo for a couple of minutes before introducing the tomatoes and saffron to the pan.
Add half the stock. Simmer gently, giving it an occasional stir, until the stock is absorbed.
Add the rest of the stock in batches until the orzo is cooked through, but has a tiny bit of chewiness; this will take around 20-30 minutes. You may need a little less or more stock depending on the size of your orzo.
Add the prawns and the kale leaves and cook for a couple of minutes until the prawns are defrosted and the leaves have wilted and then serve.