For the French Onion Soup, cut the onions into strips as fine as possible. Heat the frying oil in a large pot and fry the onions until golden brown.
Add the cane sugar and caramelize the onions. Deglaze with sparkling wine (or white wine) and pour in vegetable soup. Bring to a simmer over medium heat.
Finely slice the garlic cloves and add them. Also season with salt, garlic powder, bay leaves, peppercorns and juniper berries. Simmer for a total of 40 minutes.
Toast the slices of toast and then cover them with fine slices of mozzarella and camembert. Gratinate in a contact grill (with a hold-down function) or in the oven (with top heat). Before serving, fish out the bay leaves and juniper berries from the soup.
The peppercorns can also be removed or eaten along with the soup, depending on taste. Cut the gratinated toasts into quarters and add to the soup in the soup plate. Serve the French onion soup.