Preheat the oven to 170°C and sprinkle the flour onto a small baking tray and toast for a few minutes until brown. Watch carefully as it can burn easily.

When brown, remove from the oven, stir through with a fork stir to separate, and leave to cool.

In a round flat-bottomed wok, on high heat, melt the butter then add the onion slices and stir frequently until the onions start to soften.

Season with salt, pepper and sugar, add the olive oil, combine well, turn the heat down to medium, then put the lid on, but continue to stir every few minutes or so.

Remove the lid and stir-fry the onions until they brown, scraping any caramelised onion from the base of the wok so they don’t burn. If needed, add a tablespoon of water.

When the onions are an even brown colour, turn the heat down.

Add the toasted flour to a measuring jug, then add 100ml of boiling water, whisk to ensure there are no lumps, then add to the onions, and combine.

Gradually stir in the white wine and half the cold water, bring to the boil, then add the rest of the cold water, and bring to a boil again.

Turn the heat down to low, add the star anise and fish sauce, then simmer for another 5 minutes or so. Taste and adjust the seasoning to suit your palate.

Grill the baguette slices on a baking tray, toasting them on both sides until golden.

Divide the onion soup between the bowls, pop a couple of baguette slices onto the top of the soup of each bowl, sprinkle the grated Comté cheese onto the baguette slices.

Places the bowls onto the baking tray and return to the grill until the cheese has melted and is bubbling, and serve immediately with more freshly ground black pepper and sea salt.