Set a large, deep, wide pan with a lid over a medium heat, add the butter and melt completely. When it begins to foam, add the leeks, cover the pan with the lid and cook for 5 minutes, stirring occasionally to stop them sticking and make sure they cook evenly. When you remove the lid, the onions should look quite moist.
Increase the heat slightly, remove the lid and continue cooking. Add the brown sugar or treacle and stir in – the moisture will evaporate and the caramelisation will begin.
Cook the leeks for another 20–30 minutes, stirring every so often, until they start to caramelise to a golden brown. Add the garlic and chutney to the pan, followed by the flour. Mix well and cook for a couple of minutes before pouring in the stock and ale, a little at a time, mixing well each time you add some. Bring the soup to a simmer and add the bunch of herbs. Cook for around 15 minutes, turn down the heat and simmer for another 10 minutes. Taste and season with salt and pepper if required.
While the soup is simmering, make the rarebit. Preheat the grill to hot and line the grill pan with foil. Mix the butter with the mustard, ale and cheese in a small pan and melt slowly over a gentle heat, allow to cool, then chill in the fridge for 20 minutes to thicken. Cut each slice of bread in half, toast on one side and rub with the bruised garlic. If the croûtes seem too big, cut each one into two again. Beat the egg yolks into the cooled cheese mixture and spoon over the untoasted side of the croûtes. Don’t worry if it looks a little lumpy at this stage.
Arrange the croûtes on the lined grill pan and heat under the grill for 2-3 minutes until browned and bubbling. Meanwhile, divide the soup among four large serving bowls. Remove the croûtes from the grill, taking care as they will be very hot, and add one (or two if you sliced them in two) to each bowl of soup.
Sprinkle the chopped parsley and thyme over, add a good dollop of the caramelised onion chutney and serve immediately.
Recipes by Maxine Clark, food styling by Lizzie Harris, Photography by Peter Cassidy, props styling by Angela Dukes
