In a nonstick skillet, heat oil over medium-high heat. Add chicken, in batches; brown on all sides. Transfer to a crockpot.
Reduce heat to medium. to skillet, add onions and cook, stirring, until softened. Add garlic, chile pepper, curry, oregano, salt and peppercorns and cook, stirring, 1 minute. Stir in chicken broth, tomato sauce and bay leaf; bring to a boil.
Pour mixture over chicken. Cover and cook on LOW for 6 hours or on HIGH for 3 hours, until juices run clear when chicken is pierced with a fork.
In a bowl, combine peanut butter and sherry. Add a little cooking liquid; stir to blend. Add to crockpot along with bell pepper. Cover and cook on HIGH for 20 minutes, until bell pepper is tender. Discard bay leaf.
Serve over rice.
Make ahead: This dish can be partially prepared the night before it is cooked. Complete Step 2, heating 1 Tbsp oil in a pan before softening onions. Cover and refrigerate overnight. The next morning, brown chicken. Continue cooking as directed.Servings: 6