Saute the onion in the butter and blended oil on high heat until they are tender and start to caramelize. Lower flame to very low and add the sugar, salt, pepper, thyme, and garlic. Sweat until garlic is cooked. Add the flour and cook until all the rawness is cooked out. Add Wine, increase flame to medium. Cook until liquid is reduced to syrup. Add the chicken stock and bring to simmer, stirring and being watchful not to burn the bottom. Simmer for 45 minutes to an hour. Adjust salt and pepper.