Sauté onion and garlic in 1 tablespoon butter and olive oil until softened. Add rice; cook and stir over medium-high heat 2 to 3 minutes to coat well. Add hot broth, 1/2 cup at a time, cooking over low heat and stirring constantly after each addition until broth is almost absorbed. Cook until rice is al dente and consistency is creamy. Remove from heat.
Just before serving, heat 1 teaspoon butter in medium pan. Add Mushroom Ragout; cook and stir until hot. Stir in 1/4 cup Truffle Wine Sauce; heat 2 to 3 minutes. Remove from heat; stir in remaining 1 teaspoon butter. Gently fold in cheese.