Season the chicken thighs with salt and black pepper according to your taste.
Warm the olive oil in a large skillet over medium-high heat and brown the chicken thighs for about 3 to 5 minutes on each side.
Combine ketchup, soy sauce, honey, dark brown sugar, grated ginger, sriracha, and minced garlic in a medium bowl and mix well.
Place the browned chicken thighs into a 6-quart slow cooker and pour the prepared sauce evenly over them.
Cover the slow cooker and cook on the high setting for 2 to 3 hours until the chicken is cooked through and the sauce is slightly reduced.
Once done, sprinkle sliced green onions and chopped cilantro over the chicken and serve it hot over cooked white rice.
