Prepare the Whipped Beans: In a large skillet, heat 1 tsp (5 ml) of olive oil over medium heat.
Add the chopped leek and sauté for 2 minutes until softened.
Stir in the cannellini beans, vegetable broth, minced garlic, and thyme.
Cover, reduce heat to low, and simmer for 8 minutes.
Season with salt and pepper. Carefully transfer the mixture to a food processor and blend until luxuriously creamy and smooth. Return the purée to the skillet, cover, and keep warm.
Cook the Wild Mushrooms: While the beans are simmering, heat the remaining 1 tsp (5 ml) of olive oil in a separate medium skillet over high heat.
Add the mushrooms and cook, stirring occasionally, for about 8 minutes until they are deeply browned and tender.
Season with salt and pepper, then remove from heat and stir in the chopped fresh parsley.
Assemble and Serve: Divide the warm whipped bean purée among four shallow bowls. Artfully arrange the sautéed mushrooms on top.
Finish each dish with a final drizzle of ½ tsp truffle oil and serve immediately.