Mix first 5 dry ingredients into a lined slow cooker or a tin that fits within your slow cooker .
Make 3 holes in dry ingredients - two small, one larger .Pour vinegar in one hole vanilla in the other and the vegetable oil in third larger hole . Pour water over all. Mix well until smooth.
Place teatowel or dish cloth or kitchen towel under lid and cook for 1 1/2 hours
Add flaked chocolate for last 10 minutes to the top if desired.