Preheat oven to 425 degrees. Line a baking sheet with parchment.
Toss butternut squash and mushrooms with maple syrup, chili powder, cinnamon, and a pinch of salt and pepper. Spread onto the prepared baking sheet. Arrange garlic cloves and rosemary sprigs in the pan. Roast 20 minutes, turning halfway through cooking time. Remove from oven and let cool until easily handled.
Pick the rosemary leaves from the stems and add to a food processor with the butternut squash and garlic cloves. Whip until pureed. You may need 1-2 tablespoons of water to get the right consistency. Move the mushrooms to a cutting board and roughly chop into 1/4 inch-ish pieces.
Warm 1 tablespoon olive oil over medium heat. Saute the shallot until fragrant, about 2-3 minutes. Pour in the orzo and toast 2-3 minutes, then add the broth or water. Bring to a boil, then lower to a simmer, cover, and cook 10-15 minutes until most of the water is absorbed and the orzo is soft. Moderate your heat level frequently: you don't want the liquid to boil off too quickly. If it does, add additional broth or water 1/2 cup at a time.
Dump in the butternut squash, coconut milk, and parmesan cheese. Stir until the cheese melts and the orzo is creamy. A few small chunks of butternut squash are okay. Divide onto plates and sprinkle with the roasted mushrooms.