01 - Preheat the oven to 425°F.
02 - In a medium saucepan, heat 1 tablespoon olive oil over medium heat. Add brown rice and toast for 1–2 minutes. Pour in vegetable broth (or water) and 1/2 teaspoon salt. Bring to a boil, then reduce heat to low, cover, and simmer for 40–45 minutes, or until rice is tender and liquid is absorbed. Remove from heat and let stand, covered, for 5 minutes.
03 - While the rice cooks, toss the quartered mushrooms with 2 tablespoons olive oil, sliced garlic, salt, and pepper on a large baking sheet. Spread in a single layer and roast in the preheated oven for 20–25 minutes, stirring once, until golden brown and tender.
04 - Fluff the cooked rice with a fork. Gently fold in the roasted mushrooms and garlic, chopped parsley, thyme, and chives (if using). Add lemon zest and toasted nuts for extra flavor, if desired. Taste and adjust seasoning with additional salt and pepper as needed. Serve warm.