Be careful when grinding the walnuts in the food processor. They should be nicely ground, but not oily.
The only slightly weird ingredient here is the fenugreek. It can be found in the spice section of a Whole Foods type store. If it is too much trouble to find, just leave it out.
Advance Prep
Make the chicken at least 1 day ahead of time and up to 3. It needs time to develop its wonderful flavor.
Source/Adapted From
Please to the Table by Anya von Bremzen & John Welchman