Place the onions into a hot saucepan with 15ml of olive oil. Cook until coloured then add the sherry and stock. Cook for 10-15 minutes.

Add the cream to the soup and season. Blitz in a liquidiser until smooth.

Pour the mixture back in the pan to warm through.

For the croutons, warm the butter in a frying pan until foaming. Add the cubes of bread and fry until golden brown.

To serve; spoon into bowls, drizzle with oil and cream.

Scatter the croutons into the soup.