Saute onions and garlic cloves in large skillet/frying pan with approx 1/4 cup oil until soft. Crush cooked garlic with spoon (while in pot). Continue cooking onions and garlic on high heat until very brown. Add chicken to the pot. Reduce heat to medium and simmer (approximately 10 minutes). Add salt, 1 teaspoon curry powder, ginger, and 1 teaspoon red pepper. Taste chicken and add spices as needed (Fehma added approx. 1 teaspoon more red pepper and 3/4 teaspoon more curry powder). Add tomatoes, chili peppers (if desired) and yogurt to chicken mixture. Cover pot and reduce heat to low; simmer. Serve with a dollup of plain yogurt, and nan bread.