You might be familiar with pappa al pomodoro, that Tuscan soup of bread, basil and sun-soaked tomatoes in summer. This recipe is a Portuguese variation of that.

Usually the bread in question is broa, a rustic cornbread given a preliminary soaking in salted water for a couple of hours. The result is soothingly porridge-like, but I like a little more structure and have thus entirely dispensed with it. I use sourdough here instead.

*A note about the stock: Reserve the prawn shells for the stock. Simmer them with an onion, a peeled carrot, a few bay leaves and a teaspoon each of salt and black peppercorns in about a litre of water for 35 minutes. Sometimes I throw in a couple of cloves and strips of lemon zest. Your call, as always.

Ingredients

• 2 tablespoons olive oil
• 400g stale sourdough bread, chunked and toasted
• 500g tiger prawns, peeled and de-veined
• A head of garlic cloves, skinned
• 2 onions, peeled and chopped
• 2 celery sticks, finely chopped
• Extra virgin olive oil
• 800ml prawn stock (see * above)
• A bunch of coriander, finely chopped
• 2 teaspoons Worchestershire sauce
• A teaspoon each of coriander and fennel seeds, roughly pounded
• Leaves from 4 thyme sprigs

Method

Brown the garlic cloves in the olive oil, in a saucepan over medium heat. Add the onion and celery and cook till soft, translucent and golden. Set this saucepan aside.

Bring the prawn stock to a simmer in a pot. Drip in the Worchestershire sauce and taste to adjust seasonings further. At this point, tip in the ground spices, thyme leaves and the toasted bread and simmer for 25 - 30 minutes, stirring occasionally. It should be thick but not too dry. Finally stir in the onion-celery medley and the cleaned prawns. The soup is done once the prawns go pink.

Serve up with a further lubrication of top-quality olive oil and a torrent of finely chopped coriander or flat-leaf parsley. Cubes or coins of fried chorizo (pork sausage) are a fetching way to cap things off, too. You cannot deny the chorizo's power to transform nearly anything Spanish or Portuguese.

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Stories and photos copyright © Bryan Koh, unless otherwise stated. Not to be reproduced without permission from the author.