Sauté the onion and garlic in a 1/2 tbsp butter until softened.
Add the risotto rice and sauté until glazed.
Add the wine and wait until the rice has absorbed it.
In a different pan sauté the mushrooms in 1/2 tbsp butter until soft.
Warm up the vegetable bouillon and to the risotto one soup spoon at a time until absorbed.
Stir the mixture until you can see that the rice is done, then add the truffle tapenade, parsley, 1/2 tbsp butter (for less calories you can skip the butter) and the parmesan cheese. Stir until the cheese and butter are melted.
Finish by adding the sautéd mushrooms. Serve right away.