Although onion soups date back to Roman times, this particular soup began life in eighteenth-century Paris as a beef broth with caramelised onions on top. Now served without the beef, the quality of the onions is crucial. You want both high acidity and high sugar levels to create a fully-flavoured soup. The best onions are Rose de Roscoff. Spanish onions, although lacking in acidity, will also work. I like to float croutons on mine, and I grate some two-year-old Comté cheese on the top. And make sure you caramelise your onions to achieve a rich, brown colour. A Frenchman's heaven!
"If you like a strong onion flavour, caramelise the onions for a further 15 minutes, until very dark brown. "
"By quickly boiling the wine, you are removing most of the alcohol, which has a bitterness, but keeping all the fruity qualities and acidity of the wine."
"You could replace the water with a brown chicken stock for a richer soup."
Recipe © Raymond Blanc 2018
Food Photography © Chris Terry 2018
Accompanying a very special BBC TV series, Raymond filmed with the Royal Botanic Gardens, Kew, this is the story of the nation's favourite fruit and veg. You’ll find an array of mouth-watering seasonal recipes, detailed tasting notes, and valuable tips for growing your own produce from the talented gardeners of Kew. A perfect read for the green-fingered gastronome.