Season the chicken thighs with the Chinese 5-spice powder.
Heat the olive oil in a large skillet over medium-high heat. Add the chicken and sear until browned on both sides, 3 to 4 minutes.
Lay the white onions in the bottom of your slow cooker pot, and place the chicken pieces on top.
Whisk the chicken broth, rice vinegar, tamari, coconut sugar, red chili flakes, and bay leaf together and pour over the chicken.
Cover and cook on low for 6 to 8 hours or high for 3 to 4 hours. When the chicken is done, add the pea pods and cook for an additional 10 minutes, or until soft.
Serve topped with the scallions.