Mix onion, coriander, garlic, ginger, turmeric, salt, cumin and pepper in a small bowl.
Coat lamb with the above mixture and marinate, covered, overnight in a medium bowl.
In a large, heavy-bottomed pot, heat oil over medium-high heat.
Add lamb, onions and spices and stir until well browned.
Add tomatoes (undrained) and coconut and bring to a boil.
Reduce heat and simmer lamb curry for 15 minutes or until sauce is thickened.
Stir in peas, capsicum and cook lamb curry until thoroughly heated.
:- Lamb Curry is ready.
:- Serve Lamb Curry warm.