Arrange the chicken thighs evenly across the bottom of your slow cooker. Keeping them in a single layer helps them cook evenly. Make sure the thighs are trimmed if necessary before placing them inside.
In a mixing bowl, combine the minced garlic, honey, ketchup, soy sauce, oregano, and fresh parsley. Whisk everything together until the ingredients are fully blended and the sauce looks smooth.
Pour the prepared sauce over the chicken thighs. Make sure each piece is coated so the flavors can soak into the meat while cooking.
Cover the crockpot with the lid and cook on LOW for 4 to 5 hours or HIGH for 3 to 4 hours. The chicken should become tender and reach a safe internal temperature of 165°F.
If you prefer a thicker sauce, mix 1 tablespoon cornstarch with 1 tablespoon cold water. Stir the slurry into the sauce about 30 minutes before the cooking time ends and continue cooking.
Carefully transfer the cooked chicken to a serving platter. Spoon the flavorful sauce over the top and sprinkle with toasted sesame seeds before serving.