French Onion and Fennel Seed

Name: French Onion and Fennel Seed
Total time: 1 h 10 min
Cuisine: British
Ingredients: 4 large onions (around 750 g), peeled and halved; 2 tbsp olive oil; 1 tbsp fennel seeds; 3 tbsp granulated sugar; 100 g salted butter, cubed; 1 leek, halved lengthwise and sliced finely; 2 garlic cloves, finely chopped; 2 tbsp plain flour; 100 ml white wine; 2 beef stock cubes; 1 chicken stock cube; 1 tbsp Marmite; 1 tbsp fresh thyme leaves; sea salt and freshly ground black pepper; sea salt and freshly ground black pepper

Preparation info

Feeds
4

Difficulty
Easy
Ready in
1 hr 10

Appears in

Cafe Cùil Cookbook

By Clare Coghill

Published 2025

About

Our take on the ultimate comfort soup. The secret to a great French onion soup is patience, as the onions can take up to 30 minutes to caramelise in the pot – but I promise it’s worth it. We like to add in a dollop of Marmite and some fennel seeds, which really intensify the flavour – give it a go!

Ingredients

4 large onions (around 750 g), peeled and halved
2 tbsp olive oil

Europe
United Kingdom
France
Scotland
Soup

Method

Begin by slicing your halved onions into slices about 5mm thick. You don’t want to slice them too thinly because they shrink once caramelised.
Heat up a large soup pot over a medium-high heat and add in your olive oil, onions and fennel seeds. Stir so they’re well coated in oil, then once they begin to sizzle add the sugar and a big pinch of sea salt.