"Create a thick Sri Lankan mango curry-inspired Thanksgiving turkey gravy using mango puree and Sri Lankan roasted curry powder. Make it savory, rich, and gravy-like rather than sweet, suitable for serving with turkey and mashed potatoes. Include imperial measurements, clear ingredients, and step-by-step instructions. Balance the mango with aromatics, stock, and a thickening method so the final texture is thick and spoon-coating. Keep it food-safe and practical for a home cook."