Chicken and Chickpea Tagine

Guys, this is so, so tasty!  I made it for the first time tonight and the family loves it too, which is saying a lot!

I found this recipe on NYT Cooking.

INGREDIENTS
2 TB corn or canola oil
2 TB butter
1 large onion, peeled and thinly sliced
2 cloves garlic, minced
Salt
Pinch nutmeg
1/2 tsp ground cinnamon
1 tsp ground ginger
1 tsp ground cumin
1 tsp ground coriander
1/2 tsp ground black pepper
Pinch cayenne
1 1/2-2 Cups chopped tomatoes (canned are fine)
4 Cups chickpeas (canned are fine, drain and rinse first)
1/2 C raisins or chopped, pitted dates
1/2 vanilla bean
8 chicken thighs
Chopped cilantro or parsley leaves

PREPARATION

1. Put oil and butter in a large skillet or casserole, which can be covered later, and turn heat to medium high. When butter melts, add onion, and cook, stirring occasionally, until it softens, 5 to 10 minutes. Add garlic, a large pinch of salt and spices. Cook, stirring, for about 30 seconds. Add tomatoes, chickpeas, raisins and vanilla, and bring to a boil. (If mixture is very dry, add about 1/2 cup water.) Taste, and add salt as necessary.
2. Sprinkle chicken pieces with salt, and nestle them into sauce. Cover, and 5 minutes later adjust heat so mixture simmers steadily. Cook until chicken is very tender, 45 minutes to an hour. Taste, and adjust seasoning. Then garnish, and serve with couscous.