Hash:
6-7 cloves garlic
1 Philadelphia inch ginger

in a blender till smooth.  Add about 1/2 C water to facilitate this. 

Brown about 3lb chicken in hot oil till brown.  Set aside till they're a little done.

Chop one onion and brown it in the above oil till very dark gold.  Add that garlic/ginger paste till the water evaporates and you start to see oil again.  

Add some spices:
1 t ground cumin
1 t ground coriander
1/4 t turmeric
1/4 t cayenne

Stir and fry for about half a minute.  Add 2 medium peeled, chopped tomatoes.

Turn the heat down to simmer and cook this whole mess for 3-4 minutes, stir in:
4 TBSP plain yogurt.

Stir this in one T at a time, making sure it's all mixed in before adding more. Otherwise it curdles. 

Then add:
1 C water
Any juice that oozed out of the chicken
1 t salt
the chicken.

Bring to a boil and cook, covered, till the meat falls off the bones.

Uncover, add:
1 t garam masala
6 TBSP whipping cream

Mix well, then cook uncovered till the sauce is reduced and thickish.