Mix onion, coriander, garlic, ginger, turmeric, salt, cumin, pepper and cayenne pepper in a small bowl. Coat lamb with mixture and marinate, covered, overnight in a medium bowl.
In a large, heavy-bottomed pot, heat oil over medium-high heat. Break chile over pan, crumbling into hot oil. Sauté lamb, scraping onions and spices into pot, until well browned. Add tomatoes (undrained) and coconut and bring to a boil. Reduce heat and simmer for 15 minutes, or until sauce is thickened. Stir in peas and cook until thoroughly heated. Serve warm.
Servings: 4