Chicken in an Amazing Tamarind Sauce

Ayam Sioh in Malay. Adapted from THE BEST OF MALAYSIAN COOKING by Mrs. Leong Yee Soo.

Mix together in a container large enough for about 1.75 pounds of chicken pieces that you can cover and put in the refrigerator overnight:
3 oz sweet onions or shallots ground in a food processor
1-1/2 Tablespoons or a bit more very fresh coriander seeds ground up (roast very lightly in a skillet, cool, then whir in a coffee/spice grinder; they lose their flavor quickly -- as in a month or two -- after grinding but are amazing when fresh)
3/4 Tablespoon sugar (unfortunately necessary)
1/2 tsp or more black pepper
3/4 tsp salt
1 Tablespoon soy sauce (Kikkoman)
3/4 Tablespoon or more tamarind paste (Southeast Asian is best, but Indian is OK)

Add 1.75 pounds of chicken thighs (with bones, but skinless if you like), coating them with the above marinade.
Marinate overnight or all day (in the refrigerator). Do NOT remove marinade.
Put a generous splash of oil (I used about 2 Tablespoons very light olive oil) in a skillet and place the chicken and its sauce/marinade in it. Saute covered until done.

Freezes super well! But don't miss some served fresh and hot from the skillet!

(from previous incarnation of this site)