Cook the spaghetti

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

Make the avocado pesto

• Scoop the avocado flesh into a blender.
• Add the garlic, parmesan, lemon juice, olive oil and basil.
• Season with salt and pepper and blend until smooth and creamy.

Combine and serve

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