1/2 teaspoon crushed red pepper flakes or to taste
1/2 cup dry sherry (I used apple cider)
4 cups low sodium chicken broth (I used low sodium vegetable broth)
1/4 cup dark maple syrup
3 tablespoons reduced-sodium, wheat-free tamari or reduced-sodium soy sauce
2 tablespoons white vinegar
1 cup large-diced carrots
1 cup large chunks peeled celeriac (I added 8 ounces rice noodles + additional 2 cups low-sodium broth at end of cooking time instead)
1 cup large chunks peeled yellow potato (I added spicy leafy greens at end of cooking time instead)
2 tablespoons toasted sesame seeds
1/4 cup thinly sliced scallions
Heat oil in a large heavy skillet over high heat. Add chicken thighs and cook for 7 to 8 minutes until browned. Flip and brown other sides. Remove skillet from heat and transfer chicken to a large slow cooker.
Return the skillet to medium-high heat. Add onions, mushrooms and garlic and cook, stirring often, 3 to 5 minutes, until onion is softened. Add five-spice powder, ginger and red pepper flakes and cook, stirring, 30 to 90 seconds, until fragrant. Add sherry and cook, scraping up any browned bits, 30 to 90 seconds, until mixture comes to a boil and sherry is reduced by about one half.
Transfer onion mixture to the slow cooker. Add broth, syrup, tamari and vinegar and stir to combine. Place carrots, celeriac and potato on top (do not stir.) Cover and cook for 4 hours on LOW. Garnish with sesame seeds and scallions and serve.