Preheat the oven to 220°C fan-forced.
Place the cavolo nero, basil, garlic and three-quarters of the cream in a high-powered blender and blitz to a green puree. Generously season with salt and pepper. Depending on the size and power of your blender, you might need to do this in two batches.
Pour the mixture into a 30cm x 20cm baking dish (or a 25cm round dish), add the lemon juice and 750ml (3 cups) of the stock and gently whisk to combine.
Tip in the risoni and gently mix to spread the pasta evenly through the liquid.
Scatter the mushroom slices on top, spreading them as much as you can, but do not mix them into the liquid.
Drizzle over the olive oil and sprinkle with some salt and pepper.
Transfer the dish to the oven and bake for 20 minutes, until the mushroom is deep golden brown and the dish is bubbling.
Remove the dish from the oven, scatter over the parmesan, then gently stir the mushrooms and cheese through the risoni.
Add the burrata whey and stir it through to combine. At this point taste the mixture and adjust the seasoning if necessary. If the risoni is still undercooked and the liquid has evaporated, add the remaining stock.
Return the bake to the oven for a final 5–10 minutes, until the pasta is just cooked.
Tear up the burrata and place it evenly over the pasta bake, nestling some pieces in the risoni.
Right before serving, spoon over the reserved cream, scatter with a few basil leaves and drizzle with a little extra olive oil.
Serve with lemon wedges.
