French Onion Gruyère Toasts

By Toby Devonshire

By Toby Devonshire

Co-Founder of Supp

Close-up of two French onion Gruyère toasts on a wooden board, caramelised onions glistening, melted golden Gruyère, fresh thyme sprigs, rustic sourdough slices, soft natural light, shallow depth of field

Prep Time

10 mins

Servings

4 Servings

Cook Time

35 mins

Difficulty

Easy
Sweet caramelised onions, melted Gruyère and a whisper of thyme make these toasts a comforting, speedy lunch.

Ingredients

2 brown onions, thinly sliced

30g unsalted butter

1 tbsp olive oil

1 tsp caster sugar

1 tbsp balsamic vinegar

50ml dry white wine

1 tsp Dijon mustard

2 per serving crusty bread (sourdough or baguette)

200g Gruyère, grated (can substitute Emmental)

A few sprigs fresh thyme

1 tsp sea salt

1/2 tsp black pepper

Method

Step 1

Peel and thinly slice the onions. Warm a large frying pan over a medium-low heat and add the butter and olive oil.

Step 2

Add the sliced onions and a pinch of salt. Cook gently for 25–30 minutes, stirring every few minutes, until the onions are soft and a deep golden brown. If they catch, lower the heat and stir more frequently.

Step 3

Stir in the caster sugar, balsamic vinegar, white wine and thyme leaves. Increase the heat slightly and simmer for 3–4 minutes until most of the liquid has evaporated. Season with salt and freshly ground black pepper to taste. Remove from the heat.

Step 4

Preheat the oven to 220ºC. Arrange the bread slices on a baking tray. If using, spread a thin smear of Dijon mustard on each slice.

Step 5

Divide the caramelised onions evenly over the bread slices, then scatter the grated Gruyère on top.

Step 6

Bake for 8–10 minutes until the cheese has melted and begun to turn golden. For a crisper top, use the grill for the final 1–2 minutes but watch carefully to avoid burning.

Step 7

Remove from the oven, scatter a few thyme leaves over the toasts and serve immediately while hot.

Nutritional Information

Per serving:

Energy - 643kcal
Protein - 25.8g
Carbohydrates - 69.3g
Fat - 31.3g
Fibre - 6.1g

This nutritional information is provided as a helpful estimate. Values may vary depending on the ingredients and portion sizes you use.

Recipe Notes

Cook the onions slowly for the best caramelisation. Substitute white wine with vegetable stock for a non-alcoholic version.

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