Heat canola oil in a medium saucepan over medium heat. Add garlic, ginger, chili powder, and onion and sauté about 3 minutes. Add soy sauce and brown sugar, and bring to a boil. Cook, covered, over medium-low heat 8 minutes or until onion is tender.
Transfer to a blender; add vinegar, ketchup, mustard, and sesame oil, and process until a chunky puree forms.
Add sauce to crockpot. Add hot dogs. Cook on high 2 hours or on low 4 hours. Serve warm and garnish with sesame seeds if desired.
Notes
Pro tip: serve straight from your slow cooker to keep them warm!