Preheat oven to 400°F.
Place mushrooms in medium bowl. Drizzle with 1 tablespoon oil and sprinkle with ½ teaspoon salt, toss to coat. Spread on sheet pan.
Place cauliflower, remaining 2 tablespoons oil, ½ teaspoon salt and chipotle chili powder in same bowl, toss to coat. Spread on sheet pan with mushrooms.
Combine sausage, preserves and mustard in same bowl; stir until well coated. Arrange sausage over vegetables; top with onion.
Roast 30 minutes. Remove from oven; place cheese cubes on top of cauliflower. Bake 5 minutes or until cheese is melted and cauliflower is tender.
