Cook the pasta

• Bring a large pot of salted water to a boil.
• Cook the pasta until al dente, then drain, keeping a little cooking water.

Make the avocado pesto

• Blend the avocado, basil, garlic, pine nuts, parmesan, olive oil and lemon juice until smooth.
• Season with salt and black pepper.

Combine and serve

• Toss the hot pasta with the avocado pesto, loosening with a splash of cooking water.
• Serve immediately with extra parmesan.