1 lb basmati rice
1.5 - 2 lb lamb, bone in (use some pieces from the ribs) --make sure
it is tender meat

Fry 2 medium onions till golden brown. Take out of the oil. Save the
oil.
Mix well the following:
the meat pieces, 
the onion, some of the oil,
3/4 tbsp ginger and garlic powders each (less if using fresh paste)
2-3 green chilies, split in two
1 stick of cinnamon, broken in 3-4 pieces
6 cardamom  pods, crushed by hand
6-8 cloves
half a handful of cilantro leaves
half tsp red chili powder
3/4 cup yogurt
1 tsp salt (more if you wish)
Keep the above mix standing for about 4 hours (in the fridge)
Boil the rice in twice as much water, till it is halfway cooked. Drain. 
Place the mix at the bottom of a baking pan (the blue pans you get here  
for roasting are good, or else an aluminum baking dish will do). Spread  
the rice on top of the mix.  Heat up a pinch of saffron in half a cup of 
milk, and spread the milk around on top. Cover the pan with its cover, 
or aluminum foil. Heat the oven to 400, and bake for about 45-60 minutes. 
Check around 45  min -- for doneness of meat --some like it a little chewy, 
others soft.  By now, the fragrance of the biryani should be wafting through 
the house,  and you should be salivating. Enjoy it with dahi ki chatni!