In a large pot of salted boiling water, cook the pasta for 6-8 minutes or until al dente. Drain, reserving 125ml of the cooking liquid.
In the jug of a blender or food processor, combine the avocado, spinach, almonds, parmesan, basil, chilli, garlic and lemon juice. Blend until smooth and creamy.
While the blender is still running, pour in the reserved cooking liquid until you reach the desired consistency – it should be quite thick in order to coat the pasta well.
Season to taste.
Toss the pasta and avocado sauce together and serve with avocado roses, olive oil, basil leaves and chopped almonds.