In a 5 - 7 quart slow cooker stir together coconut milk, chicken broth, red curry paste, brown sugar, coriander, cumin, ginger and garlic. Season lightly with salt (about 1/4 tsp).
Add chicken, carrots and onions to slow cooker and submerge lemongrass in broth. Cover and cook on low heat until chicken is cooked through and tender, about 5 hours, while adding in bell pepper during last 45 minutes of cooking.
Remove chicken from slow cooker and let rest a few minutes then shred. Remove lemongrass if used.
Season with a little more salt to taste (I needed another 1/4 tsp). Serve warm with rice, sprinkle with peanuts and remaining cilantro.