1. In a pot, sauté the mandolin sliced large onions over medium heat. Keep stirring for a good 30 minutes 2. Add the flour and stir for another couple of minutes 3. Deglaze with the broth and crank up the heat, remove just before the pot starts showing signs of boiling 4. Set the oven on combi at 80°C 5. Place in the oven and cook for 45 minutes 6. Correct the seasoning 7. Transfer the soup into eight heated ovenproof bowls and place two slices of toasted bread in each portion 8. Set the oven on dry heat at 180°C using the Golden Touch function 9. Sprinkle the cheese over the toasted bread and bake until the cheese is melted and golden