Arrange chicken in the slow cooker; season with salt and pepper.
Pour chicken broth into the bottom of the slow cooker.
Cover and cook on LOW until the chicken is easily shred-able (3-8 hours).
Transfer chicken to a cutting board, shred it, and drain the liquid from the slow cooker.
Wipe out any excess fat and return shredded chicken to the slow cooker.
In a medium bowl, whisk together coconut milk, peanut butter, garlic, honey, soy sauce, lime juice, rice wine vinegar, fish sauce, and crushed red pepper flakes until smooth.
Pour the sauce over shredded chicken; stir to coat.
Cover and cook on LOW for up to 1 hour, stirring halfway, until sauce thickens and everything is heated.
Serve over rice, rice noodles, or lettuce leaves; garnish with chopped peanuts and fresh cilantro.