Heat the sesame oil in a large saucepan over medium-high heat. Saute the ginger, garlic and green onions until fragrant, about 1 minute. Add the brown sugar, chili sauce, soy sauce, vinegar, honey and 1/2 cup water. Whisk until fully incorporated. Bring to a simmer over medium-high heat, stirring occasionally. Continue cooking until the sauce has thickened, about 5 minutes. Remove from the heat and let cool.
Sprinkle the ribs liberally with salt and pepper and place in an upright position in the slow cooker. The meaty side should be facing outwards. Spoon the sauce over the ribs and cook on high for 3 to 4 hours or on low for 6 to 8 hours.
Strain the sauce from the slow cooker into a saucepan and remove any accumulated grease from the top. Combine 1 tablespoon water with the cornstarch and whisk together in a small bowl. Add the mixture to the saucepan and bring to a boil over medium-high heat. Reduce the sauce until thickened and serve with the ribs.
For a crisper texture, slather the ribs in the reduced sauce and char (meaty-side down) on a hot grill or under the broiler, 1 to 2 minutes per side, before serving with the remaining sauce.