Adjust rack to middle position (middle and top positions for 4 servings) and preheat oven to 425 degrees. Wash and dry produce.

Trim and quarter mushrooms (skip if your mushrooms are pre-sliced!). Dice tomato into ½-inch pieces.

In one oven-ready tray, toss mushrooms with a drizzle of oil, salt, and pepper (for 4 servings, divide mushrooms between two trays).

In remaining oven-ready tray, combine rice, veggie stock concentrate, mushroom stock concentrate, cream cheese (it's OK if it clumps!), and 1¾ cups water (for 4 servings, divide everything between remaining two trays, using 1¾ cups water for each tray); stir until well combined.

Sprinkle rice mixture with tomato, then arrange spinach over top (for 4, divide tomato and spinach between trays). TIP: Evenly spread out spinach and press down, making sure no leaves hang over the edges of your tray!

Cover rice tray tightly with foil. Bake both trays, side by side, on middle rack (be sure your oven has preheated!) until rice is cooked and mushrooms are tender, 30-35 minutes. (For 4, bake trays with rice mixture on top rack and trays with mushrooms on middle rack.)

Once rice is done, carefully remove and discard foil (watch out for steam!). Stir in garlic herb butter (divide between rice trays for 4 servings). 

Transfer roasted mushrooms to tray with rice; stir until everything is combined and creamy. TIP: If risotto seems too thick, stir in a splash of water.

Taste and season with salt and pepper if desired.

Divide risotto between shallow bowls. Sprinkle with Parmesan and serve.