For the spaghetti with garlic parsley pesto, cook the spaghetti in plenty of boiling salted water for about 10 minutes until al dente. Then pour into a colander, rinse with cold water and drain well.
For the pesto, lightly toast the pine nuts in a pan without fat. Peel and chop the garlic cloves. Wash the parsley, pat dry and pluck the leaves. Mix the three ingredients well, add 2 tablespoons of olive oil, 2 tablespoons of water and some salt and puree finely.
Peel the spring onion, wash and cut into fine rings. Halve chili pepper, remove seeds and chop finely. Heat 1 tablespoon of olive oil in a pan and sauté the spring onion rings until translucent. Add the drained spaghetti, chili pepper and pesto and toss for 4-5 minutes.
Season to taste with salt and pepper. Divide the spaghetti with garlic-parsley pesto among the warmed serving plates, sprinkle with grated Parmesan and serve immediately.