In a large pot, sauté the shallots and rice in the butter for 5 minutes until the shallots are translucent but not browned. Gradually add the vegetable bouillon, stirring constantly until all the liquid is soaked up before adding more.
In another pan, sauté the wild mushrooms with the rosemary and garlic and season with salt and pepper. When the rice is almost cooked and all the boullion has been used up, stir in the mushrooms. Add the tarragon, cream and half the parmesan shavings and season to taste.
To serve, place some risotto in a large bowl and drizzle lightly with the truffle oil. Dress the rocket leaves with the red onion dressing and place a little on top of the risotto. Garnish with the rest of the Parmesan shavings.