Gratinated Onion Soup

Method

1. Cut the red onions coarsely (not too thick nor too fine).
2. In a pan with high sides, melt two knobs of butter with a drizzle of extra virgin olive oil over medium heat.
3. Add the onions a little at a time, letting each batch wilt before adding more. This keeps the temperature constant and reduces cooking time.
4. Season with a pinch of salt (do not over-salt, as the cheese will add more).
5. Add enough vegetable broth to just cover the onions. Cover the pan, leaving the lid slightly ajar, and cook over medium heat for about 30 minutes. If it dries out, add more broth.
6. Meanwhile, cut fresh bread into slices about 1 cm thick.
7. Toast the bread slices in a pan with a knob of butter and pepper. Melt the butter without letting it burn, add the bread, let it absorb the butter, then flip quickly. Set aside.
8. In a baking dish (earthenware or ovenproof dish), arrange the toasted bread slices in a single layer to cover the base. Sprinkle with a little grated Parmigiano Reggiano.
9. Once the onions are caramelized and creamy, spread them over the bread layer.
10. Grate more Parmigiano over the onions, then cover with slices of Emmental or Edam cheese.
11. Finish with another dusting of grated Parmigiano.
12. Bake in a preheated oven using the grill function until the surface is golden and bubbly.
13. Serve immediately.