Heat some olive oil in a large pan over medium-high heat. Add the minced garlic and sauté for 30 seconds. Add the sliced mushrooms and cook until they’re soft and browned, about 5-7 minutes. Season with salt, pepper, and parsley. Set aside.
In the same pan, heat the remaining tablespoon of olive oil over medium heat. Add the finely chopped onion and sauté until soft and translucent, about 2-3 minutes.
Add the Arborio rice to the pan with the onions. Stir the rice for about 1 minute, coating it with the oil and allowing it to become slightly toasted. Season with a pinch of salt and pepper.
Pour in the white wine and stir constantly until it has mostly evaporated. This step adds depth of flavor but is optional.
Begin adding the warm stock, one ladleful at a time. Stir frequently, allowing each addition of stock to be absorbed before adding the next. Continue this process for about 18-20 minutes, until the rice is creamy and al dente.
Once the rice is cooked, stir in the sautéed mushrooms, butter, and grated Parmesan. Mix until the cheese melts and the risotto becomes rich and creamy. Taste and adjust seasoning if needed.
Serve the risotto hot, garnished with a sprinkle of parsley and a drizzle of truffle oil or shavings, if using.
