To prepare the purple pesto, start by blanching the red cabbage. Chop the cabbage into smaller pieces and quickly dunk them in a pot of boiling water. Let them blanch for a short time to remove the raw harshness while preserving the vibrant purple colour. Immediately transfer the cabbage to a bowl of icy cold water to stop the cooking process and lock in the bright hue.

Once the cabbage is cooled, drain it well and transfer it to a blender. Add the pine nuts, Parmesan cheese, and a generous handful of basil leaves. Drizzle in some olive oil to help the mixture blend smoothly. Blend until you achieve a creamy, rich pesto consistency, adjusting with a little more oil if needed.

In a large mixing bowl, toss the pre-cooked spaghetti with the freshly made purple pesto, ensuring the pasta is evenly coated. Garnish with extra basil leaves, a sprinkle of Parmesan, and a crack of black pepper for added flavour.

Serve immediately and enjoy.