1. Roast the hazelnuts in the oven for 10 minutes on 180C. Allow to cool.
2. In a food processor blend the hazelnuts, coriander, garlic, 1/4 cup parmesan cheese and olive oil. Squeeze about 1 tbs of fresh lemon juice on top and add salt & pepper to taste. Pulse to combine.
3. Boil the tortellini in salted water until cooked. Drain the tortellini. Add the pesto and stir. Garnish with parmesan.