indian chicken curry

Excellent chicken curry!

indian chicken curry (adapted from food network)
2 tablespoons red wine vinegar
1 tablespoon tomato paste
2 teaspoons garam masala
2 teaspoons curry powder
2 cloves garlic, minced
1 (14.5) ounce canned petite diced tomatoes
1 1-inch piece of fresh ginger, peeled and cut into pieces
kosher salt and freshly ground black pepper
5 boneless, skinless chicken breasts (mine were frozen)
1 (5 ounce) package baby spinach (dang, I forgot!)
chopped fresh cilantro for garnish
hot cooked jasmine rice or naan bread for serving

Combine the vinegar, tomato paste, garam masala, curry powder, garlic, tomatoes with their juices, ginger, 1/2 teaspoon salt and 1/4 teaspoon pepper in a blender.  Puree until well blended and only slightly chunky.
Spray the slow cooker with non-stick spray.  Place chicken on the bottom of the slow cooker.   Sprinkle generously with salt and pepper. Pour the sauce over the top.  Cook on high for 6 hours.
Stir in the baby spinach until wilted, if using.  
Serve with cilantro, rice and naan bread.