Leek and Potato Tart Recipe

<ul class="ingredients-main-list"><li class="ingredients-single-item">For the pastry:</li><li class="ingredients-single-item">200g plain flour</li><li class="ingredients-single-item">100g cold unsalted butter, cubed</li><li class="ingredients-single-item">1/4 tsp salt</li><li class="ingredients-single-item">3-4 tbsp ice-cold water</li><li class="ingredients-single-item">For the filling:</li><li class="ingredients-single-item">3 medium leeks (about 400g), cleaned and thinly sliced</li><li class="ingredients-single-item">2 medium potatoes (about 350g), peeled and thinly sliced</li><li class="ingredients-single-item">25g unsalted butter</li><li class="ingredients-single-item">2 tbsp olive oil</li><li class="ingredients-single-item">2 cloves garlic, minced</li><li class="ingredients-single-item">2 tsp fresh thyme leaves (or 1 tsp dried)</li><li class="ingredients-single-item">For the custard:</li><li class="ingredients-single-item">3 large eggs</li><li class="ingredients-single-item">200ml double cream</li><li class="ingredients-single-item">100ml whole milk</li><li class="ingredients-single-item">100g Gruyère cheese, grated (or mature Cheddar)</li><li class="ingredients-single-item">1/4 tsp freshly grated nutmeg</li><li class="ingredients-single-item">Salt and freshly ground black pepper</li></ul>

<ul class="equipment-main-list"><li class="equipment-single-item">23cm loose-bottomed tart tin</li><li class="equipment-single-item">Baking beans or dried pulses</li><li class="equipment-single-item">Baking parchment</li><li class="equipment-single-item">Mandoline (optional, for slicing potatoes)</li></ul>

<ol class="no-list-style"><li class="MethodStepper"><h4 class="step-title">Step 1</h4>Make the pastry by placing the flour, salt and butter in a food processor. Pulse briefly until the mixture resembles breadcrumbs (or rub the butter into the flour by hand). Add the ice-cold water a tablespoon at a time, pulsing between additions, until the dough just comes together - the cold water prevents the butter from melting, which is crucial for a flaky texture.</li><li class="MethodStepper"><h4 class="step-title">Step 2</h4>Turn the dough onto a lightly floured surface, shape into a disc, wrap in cling film and refrigerate for at least 30 minutes. This resting period relaxes the gluten in the flour, preventing the pastry from shrinking during baking.</li><li class="MethodStepper"><h4 class="step-title">Step 3</h4>While the pastry chills, prepare your filling. Heat the butter and oil in a large frying pan over medium-low heat. Add the sliced leeks with a pinch of salt and cook gently for 15-20 minutes until completely soft but not browned. Patience is key here - properly softened leeks will create a sweet, mellow flavor base.</li><li class="MethodStepper"><h4 class="step-title">Step 4</h4>When the leeks are soft, add the garlic and thyme and cook for another 2 minutes until fragrant. Remove from heat and allow to cool slightly.</li><li class="MethodStepper"><h4 class="step-title">Step 5</h4>Preheat your oven to 190°C/170°C fan/Gas 5. Roll out the chilled pastry on a lightly floured surface to about 3-4mm thickness, making it large enough to line your tart tin with a little overhang. The thinness is important for achieving a crisp base that can support the filling.</li><li class="MethodStepper"><h4 class="step-title">Step 6</h4>Carefully transfer the pastry to your tart tin, pressing it gently into the corners without stretching it. Roll your rolling pin over the top to trim excess pastry, then prick the base all over with a fork. Line with baking parchment and fill with baking beans. Blind bake for 15 minutes, then remove the beans and parchment and bake for a further 5 minutes until the base is just turning golden but not fully cooked.</li><li class="MethodStepper"><h4 class="step-title">Step 7</h4>While the pastry is blind baking, place your thinly sliced potatoes in a bowl of cold water for 5 minutes to remove excess starch, then drain thoroughly and pat dry with kitchen paper. This prevents the potatoes from discoloring and helps them cook evenly.</li><li class="MethodStepper"><h4 class="step-title">Step 8</h4>Spread the cooled leek mixture over the base of the part-baked pastry case. Arrange the potato slices in an overlapping pattern on top of the leeks - I find starting from the outside and working inward creates a beautiful pattern.</li><li class="MethodStepper"><h4 class="step-title">Step 9</h4>Whisk together the eggs, cream, milk, grated cheese, nutmeg, salt, and pepper. The custard should be well-seasoned as it will be diluted slightly by the vegetables. Carefully pour this mixture over the leeks and potatoes, allowing it to seep between the layers.</li><li class="MethodStepper"><h4 class="step-title">Step 10</h4>Reduce the oven temperature to 180°C/160°C fan/Gas 4 and bake the tart for 35-40 minutes until the filling is set with just the slightest wobble in the center and the top is golden brown. The lower temperature ensures the egg custard cooks gently without curdling.</li><li class="MethodStepper"><h4 class="step-title">Step 11</h4>Allow the tart to cool in the tin for at least 15 minutes before removing - this resting time allows the custard to fully set and makes it much easier to cut clean slices. Serve warm or at room temperature with a crisp green salad. The tart can be stored in the refrigerator for up to 3 days and reheated gently in the oven, or frozen for up to 1 month.</li></ol>