Heat butter in saucepan and saute onions until well browned.
Add chili powder, pepper, cumin, coriander and turmeric.
Stir and cook, 1 minute.
Add lentils, lemon juice, broth and coconut if using.
Bring to boil, reduce heat and simmer for 45-55 minutes (if mixture is too thick, you may need to add a little hot water).
Steam broccoli for 7 minutes.
Plunge broccoli in cold water and set aside.
Remove ⅓ cup of liquid from the lentil mixture.
Add to flour to form a smooth paste.
Return to pan; add broccoli, salt and nuts if using.
Simmer for 5 minutes.
Serve over Basmati rice.
