Wash the basil leaves thoroughly and drain the water.
Finely chop the onion.
Heat olive oil in a pan and sauté the onion.
Add the rice and cook until it becomes translucent.
Pour in the white wine and let the alcohol evaporate.
Gradually add warm chicken stock while cooking the rice.
When the rice is almost done, mix in the basil pesto.
Stir in some Parmesan cheese and butter and finish by mixing gently.