Wash and dry produce (except cauliflower rice). • Trim and thinly slice mushrooms. Trim and thinly slice scallions, separating whites from greens; mince whites. Peel and mince or grate garlic.
Place cauliflower rice in a medium microwave-safe bowl (use a large bowl for 4 servings); season with 1 tsp salt (2 tsp for 4). Cover bowl with plastic wrap and poke a few holes in wrap. Microwave until tender, 5 minutes. Carefully uncover (watch out for steam!); set aside. • Meanwhile, heat a large drizzle of oil in a large pan over medium heat. Add mushrooms and season with ½ tsp thyme (1 tsp for 4). Spread into an even layer; cook, stirring occasionally, until browned and tender, 6-8 minutes (depending on the size of your pan, you may need to work in batches). Season with salt, pepper, and a pinch of truffle zest (you’ll use the rest later). • Remove pan from heat. Reserve half the mushrooms in a small bowl, leaving remaining in pan. Cover bowl with reserved mushrooms with plastic wrap to keep warm.
Heat a drizzle of oil in pan with remaining mushrooms over medium-high heat. Add scallion whites, garlic, cauliflower rice, and a big pinch of salt; cook, stirring, until fragrant, 1-2 minutes. • Add stock concentrates and ½ cup water. Cook, stirring, until water has mostly absorbed, 2-3 minutes. • Reduce heat to low. Stir in cream cheese, sour cream, 2 TBSP butter (4 TBSP for 4 servings), and remaining truffle zest to taste (we like to use it all!). • Stir in Parmesan; season with salt and pepper. TIP: If “rice-otto” is too thick, add a splash of water; for an extra-rich experience, stir in an additional 1 TBSP butter (2 TBSP for 4).
Divide cauliflower “rice-otto” between bowls. Top with reserved mushrooms and scallion greens. Serve.