Combine the farro and broth in a large saucepan over medium heat. Simmer until the farro is tender and has a creamy consistency, about 20 to 25 minutes. Season with salt and pepper, then cover and keep warm.

Place the portobello and assorted mushrooms in a large microwave-safe bowl and cover tightly. Microwave until the mushrooms are tender and have released their liquid, 6 to 8 minutes. Drain the mushrooms through a colander, reserving all the mushroom juices in a separate bowl.

Heat the oil in a Dutch oven over medium-high heat until the oil shimmers. Add the onion and porcini and cook until the onion is softened and lightly browned, 5 to 7 minutes. Stir in the drained mushrooms and cook, stirring frequently, until the moisture has evaporated and the mushrooms are well-browned, about 5 minutes.

Stir in the garlic and thyme and cook until fragrant. Pour in the Madeira and the reserved mushroom juices, scraping the bottom of the pot to release any flavorful browned bits.

Add the tomatoes and their juice and simmer gently until the sauce has thickened slightly, about 8 minutes. Remove the pot from the heat, stir in the parsley, and season with salt and pepper to taste.

Divide the warm farro into four individual serving bowls and top with a generous portion of the mushroom mixture. Serve hot.