Heat the olive oil and butter in your wide pan over medium heat until shimmering and fragrant. Add the chopped onion and sauté until translucent, about 5 minutes, until it releases a gentle aroma and turns slightly golden.
Add the sliced mushrooms to the pan, stirring occasionally. Cook until they release their moisture and develop a deep, caramelized brown hue, about 8 minutes. Their earthy aroma should fill the kitchen as they turn golden and fragrant.
Stir in the Arborio rice, toasting it gently for about 2 minutes. You’ll notice the grains becoming slightly translucent around the edges, coated in the butter and oil mixture. This step helps build a rich base for the risotto.
If using, pour in the white wine and stir until it’s mostly absorbed, about 2 minutes. The wine adds a bright, slightly tangy note that balances the earthy mushrooms.
Begin adding the warm vegetable broth, about half a cup at a time. Stir constantly, allowing each addition to be absorbed by the rice before adding more. Continue this process, stirring gently, until the rice is tender yet still has a slight bite, about 20-25 minutes.
Check the rice for doneness—aim for a creamy texture that coats the back of your spoon with a slight firmness in the center. If needed, continue adding broth and stirring until perfect.
Remove the pan from heat and stir in the grated Parmesan cheese. Season with salt and freshly ground pepper to taste. The cheese melts into the risotto, adding a rich umami flavor and silky texture.
Let the risotto rest, covered, for 2 minutes. This brief pause allows the flavors to meld and the creamy texture to settle.
Garnish with additional Parmesan or fresh herbs if desired, then serve immediately to enjoy that luscious, velvety risotto at its best.
