Serves 2 (generously)
Prep: 15 min
Cook: 20 min

2 tbsp canned Eazy fried onions or 1 chopped onion fried in 1 tbsp olive oil
125g spring onions
3 garlic cloves
4 rashers dry-cured, smoked back bacon
500g potatoes
1 unwaxed lemon
4 sprigs thyme
2 chicken stock cubes
100g watercress
10g flat leaf parsley

Boil the kettle. Cook the onion while you peel and finely slice the garlic in rounds, and trim and thinly slice the spring onions, green and all. Slice the bacon into strips and stir all into the soft onion. Season with a pinch of salt and cook for a few minutes, stirring occasionally, until the spring onion is soft and bacon cooked. Peel the potatoes, rinse and cut into chunky slices about the size of a 50p coin. Remove the zest from the lemon with a potato peeler in paper-thin scraps. Stir the unrinsed slices of potato (the starch will help to thicken the soup), lemon zest and thyme into the onions.

Dissolve the stock cubes in 1 litre of boiling water from the kettle. Stir the stock into the vegetables, return to boil, establish a steady simmer, partially cover the pan and cook briskly for 15 minutes or until the potatoes are tender. Taste and adjust the seasoning with salt, pepper and lemon juice. Discard the thyme stalks. Chop the watercress and parsley. Stir into the soup and serve.

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