Creamy leek and potato soup with potato peel crisps

This soup is silky, gently sweet from leeks, bright with lemon, and lifted by herby carrot-top pesto for a proper comforting vegetarian supper – comfort in bowls.

This creamy leek and potato soup dish scores a Nutri-Score B. The leek and potato soup gets plenty of credit for its high vegetable content from leeks, potatoes, carrot tops, basil and aromatics, while the potato peel crisps keep food waste low. The butter, olive oil, crème fraîche and soft potato rolls make it richer, so this creamy potato soup stays in the good-but-hearty zone rather than the very light one.

Estimated nutrition per serving: 1120 kcal, fat 49g, saturates 13g, carbs 140g, sugars 12g, fibre 11g, protein 25g, salt 2.1g.

Method

1. Stage 1 – Blend the carrot-top pesto (10 minutes, make ahead if you like). Put the washed carrot tops, basil, seeds, nuts, garlic, nutritional yeast and 2 tablespoons of cold water into a food processor. Blend on a low speed, then pour in the olive oil bit by bit as you increase the speed. Stop when the pesto looks mostly smooth but still has a little texture. Set it aside. If you want a head start, make this earlier in the day and chill it.
2. Stage 2 – Crisp the potato peelings (12 minutes, overlaps with the soup prep). Heat the oven to 180C/160C Fan/Gas 4. Use a vegetable peeler to pull the potato skins into long thin strips. Soak them in iced water for 5 minutes, then drain well and spread them on a lined baking tray. Bake for about 7 minutes until crisp and golden. Keep an eye on them because they turn quickly right at the end. Set the potato peel crisps aside.
3. Stage 3 – Start the leek and potato soup base (10 minutes). Warm the olive oil in a large saucepan over a medium heat. Add the potatoes, leeks, salt and black pepper, then cook for 8 to 10 minutes, stirring now and then, until the leeks soften and the potatoes start to catch a little around the edges. That gentle colour gives the creamy leek and potato soup a fuller flavour.
4. Stage 4 – Build the flavour and simmer the soup (15 minutes). Add the bay leaf, turmeric, garlic, ginger and shallot. Cook for 3 to 5 minutes until everything smells sweet and savoury. Turn the heat up, pour in the vegetable stock and bring the soup to the boil, then lower the heat and simmer for 8 to 10 minutes until the potatoes are tender.
5. Stage 5 – Wake up the yeast for the potato rolls (5 minutes, easy to do while the soup simmers). In a small bowl, whisk together 300ml warm water, the active dried yeast and caster sugar for about a minute, just until the sugar dissolves. Leave it for 5 minutes until it looks foamy. If it foams, you are in business.
6. Stage 6 – Mix and knead the dough (10 minutes). Put the flour and salt in a large bowl. Add the yeast mixture, 60g of the butter and the mashed potatoes, then mix until a dough forms. Knead by hand until smooth and supple. It will feel soft, and that is exactly what gives these potato rolls their lovely fluffy centre.
7. Stage 7 – Let the dough rise (about 1 hour, hands-off and perfect for getting ahead). Shape the dough into a ball, lightly grease the bowl with vegetable oil, then return the dough to the bowl and cover it with a clean tea towel. Leave it in a warm spot until doubled in size. During this time, you can tidy up, set the table, or simply let the soup sit. It reheats well.
8. Stage 8 – Blend the creamy leek and potato soup (5 minutes, can hold warm). Take the soup off the heat and remove the bay leaf. Add the lemon zest and juice, then blend with a stick blender until smooth and creamy. If the soup feels thicker than you want, add a splash more stock and blend again. Taste and adjust the seasoning. Keep the leek and potato soup warm over the lowest heat.
9. Stage 9 – Shape and prove the potato rolls (35 to 45 minutes, overlaps with reheating the soup). Grease a 33 x 23cm baking tin with vegetable oil and dust the work surface lightly with flour. Knock the air out of the dough, divide it into 12 even pieces and shape each one into a ball. Arrange them in the tin, then leave them to prove for 30 to 45 minutes until puffy.
10. Stage 10 – Bake the rolls until golden (25 minutes). Heat the oven to 200C/180C Fan/Gas 6. Melt the remaining 30g butter and brush it all over the tops of the rolls, then sprinkle with flaky sea salt. Bake for 25 minutes until golden brown and cooked through. If you tap the underside of one, it should sound hollow. Move them to a wire rack and let them cool just enough to handle.
11. Stage 11 – Finish and serve the soup (5 minutes). Ladle the creamy leek and potato soup into four bowls. Top each one with a handful of potato peel crisps, 1 teaspoon of extra-virgin olive oil, 1 tablespoon of crème fraîche and 1 tablespoon of carrot-top pesto. Serve straight away with the warm soft potato rolls on the side. That mix of silky soup, crunchy crisps and fluffy bread is what makes this creamy leek and potato soup such a proper meal.