If chicken thighs are large, cut them into smaller pieces.
Place chopped onion in the bottom of your slow cooker. Add chicken on top.
In a separate bowl, whisk together minced garlic, ginger, coconut milk, chicken broth, soy sauce, brown sugar, curry powder, turmeric, cumin, coriander, and red pepper flakes.
Pour the sauce over the chicken and onions in the slow cooker. Stir gently to coat the chicken.
Cover and cook on low for 6-8 hours, or on high for 3-4 hours, until chicken is very tender.
Remove chicken from the slow cooker and shred it using two forks.
Return shredded chicken to the slow cooker. Stir in lime juice.
Serve hot over rice, garnished with fresh cilantro.