I love a good sandwich. And no one does a sandwich quite like the French. This recipe combines French onion soup and the croque madame. It's like the ultimate grilled cheese sandwich. 






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I first time I ever ordered a croque madame, I was in France and I thought, “ooh, it says ‘Madame’ on it, oh la la”.  it came out, and it was a ham and cheese sandwich.  And it was the best ham and cheese sandwich I’d ever had. So, I wanted to do a croque madame. But I also wanted to add more French flavour, so in addition to doing that sandwich, I’m also stuffing it full of French onions - caramelized onions with the flavour of French onion soup.



  • 4 onions, thinly sliced
  • 2 garlic cloves, unpeeled
  • 4 sprigs thyme
  • 2 tbsp + 1 tsp (45 ml) olive oil
  • 1½ tbsp (30 ml) brandy
  • 3 tsp (15 ml) maple syrup
  • Kosher salt
  • Freshly ground black pepper
  • 1 tsp white wine vinegar



  • 1½ cups (375 ml) milk
  • 1½ tbsp (21 g) butter
  • 1½ tbsp flour
  • 1 tsp kosher salt
  • ¼ tsp freshly ground black pepper
  • ½ tsp herbes de Provence
  • Pinch freshly grated nutmeg
  • ¼ cup (25 g) finely grated Parmigiano-Reggiano (parmesan) cheese
  • 1¼ cups (150 g) grated Gruyere or Emmental cheese, divided
  • 8 slices sourdough multigrain or rye, toasted
  • 4 tsp Dijon mustard
  • 8 thin slices (about 150 g) ham, optional
  • 4 eggs
  • Butter, for frying eggs
  • Fresh thyme, for garnish

Cook's notes

Oven temperatures are for conventional; if using fan-forced (convection), reduce the temperature by 20˚C. | We use Australian tablespoons and cups: 1 teaspoon equals 5 ml; 1 tablespoon equals 20 ml; 1 cup equals 250 ml. | All herbs are fresh (unless specified) and cups are lightly packed. | All vegetables are medium size and peeled, unless specified. | All eggs are 55-60 g, unless specified.


  1. For the onions, preheat oven to 160°C (325°F). Scatter the onions onto a rimmed baking sheet along with the garlic and thyme. Drizzle with olive oil, brandy and maple syrup. Season with salt and pepper and toss to combine. Cover tightly with foil and transfer to the oven for 2 hours.
  1. Remove the foil and stir in the vinegar. Return to the oven for 15 to 20 minutes or until caramelised. Season to taste with more salt and pepper, if needed, and set aside.
  1. Set your grill (broiler) to low and line a baking sheet with foil.
  1. For the mornay sauce, in a small saucepan, heat the milk over medium-low, until steaming.
  1. Melt the butter in a medium saucepan over medium heat. Sprinkle in the flour and cook, whisking for 1 minute. While whisking, slowly add the milk. Add salt, pepper, Herbes de Provence and freshly grated nutmeg. Bring to a simmer and cook, stirring occasionally, for 1 to 2 minutes, until thickened. Remove the sauce from the heat and whisk in the Parmigiano-Reggiano and ¼ cup of Gruyere or Emmental.
  1. Lay half of the bread out on the prepared baking sheet and spread 1 tsp of Dijon over each slice. Top each with two slices of ham, if using, about 3 tbsp caramelized onions (see Note), and divide half of the cream sauce overtop. Scatter about 2 tablespoons of grated Gruyere or Emmental over each and sandwich with another piece of bread. Spread the remaining cream sauce over the tops of each sandwich and scatter over the remaining cheese.
  1. Grill the sandwiches for 4 to 6 minutes or until golden brown and bubbling.
  1. Meanwhile, fry the eggs in a little butter over medium-high heat until crisp around the edges, leaving the yolks runny.
  1. Top the sandwiches with the fried eggs, scattered with a few fresh thyme leaves and season with some extra salt and pepper.



• Leftover caramelised onions will keep tightly sealed in the fridge for up to four days.