Farro with Roasted Mushrooms

Name: Farro with Roasted Mushrooms
Ingredients: 1 cup farro or farro piccolo; 1 bunch medium mature spinach (about 8 ounces), stems trimmed; Kosher salt; ½ cup olive oil, divided, plus more for drizzling; 2 medium shallots, peeled, halved lengthwise; 2 garlic cloves, crushed; 2 sprigs thyme; 2 bay leaves; 4 tablespoons unsalted, roasted peanuts, divided; 8 ounces shiitake mushrooms, torn into bite-size pieces; 8 ounces oyster mushrooms, torn into bite-size pieces; 2 tablespoons fresh lemon juice, divided