Sweet Potato and Sage Quiche 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">2 medium sweet potatoes (about 400g), peeled and thinly sliced</li><li class="ingredients-single-item">1 large onion, finely sliced</li><li class="ingredients-single-item">2 tbsp olive oil</li><li class="ingredients-single-item">15g fresh sage leaves, 10 leaves kept whole, rest chopped</li><li class="ingredients-single-item">3 large eggs</li><li class="ingredients-single-item">250ml double cream</li><li class="ingredients-single-item">75ml whole milk</li><li class="ingredients-single-item">100g Gruyère cheese, grated (or mature cheddar)</li><li class="ingredients-single-item">1/4 tsp grated nutmeg</li><li class="ingredients-single-item">1/2 tsp salt</li><li class="ingredients-single-item">1/4 tsp freshly ground black pepper</li></ul>

<ul class="equipment-main-list"><li class="equipment-single-item">23cm loose-bottomed fluted tart tin</li><li class="equipment-single-item">Baking beans or rice (for blind baking)</li><li class="equipment-single-item">Baking parchment</li><li class="equipment-single-item">Mandoline or sharp knife for slicing sweet 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, butter and salt in a food processor. Pulse until the mixture resembles fine breadcrumbs (or rub the butter into the flour by hand). Add just enough ice-cold water to bring the dough together – it should be soft but not sticky. Cold ingredients and minimal handling are crucial for a flaky crust, as they prevent the butter from melting too quickly.</li><li class="MethodStepper"><h4 class="step-title">Step 2</h4>Form the dough into a disc, wrap in cling film and chill for at least 30 minutes. This resting period relaxes the gluten and firms up the butter, resulting in a more tender pastry that won't shrink excessively during baking.</li><li class="MethodStepper"><h4 class="step-title">Step 3</h4>Preheat your oven to 200°C (180°C fan). 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. Carefully transfer the pastry to the tin, gently pressing it into the fluted edges. Prick the base with a fork and return to the fridge for 15 minutes to firm up again.</li><li class="MethodStepper"><h4 class="step-title">Step 4</h4>Line the chilled pastry case with baking parchment and fill with baking beans or rice. Blind bake for 15 minutes, then remove the beans and paper and bake for a further 5-7 minutes until the base is just starting to color but not fully cooked. The bottom should look dry but not browned. Reduce the oven temperature to 180°C (160°C fan).</li><li class="MethodStepper"><h4 class="step-title">Step 5</h4>While the pastry is baking, prepare the filling. Heat the olive oil in a large frying pan over medium heat. Add the sliced onion with a pinch of salt and cook gently for 8-10 minutes until soft and translucent but not browned. Add the chopped sage leaves (reserving the whole ones) and cook for another minute until fragrant. Remove from the heat and set aside.</li><li class="MethodStepper"><h4 class="step-title">Step 6</h4>Bring a medium pot of water to a boil. Add the sliced sweet potatoes and blanch for 3-4 minutes until just tender but not mushy – they should offer slight resistance when pierced with a knife. Drain thoroughly and pat dry with kitchen paper. This pre-cooking ensures the sweet potatoes will be perfectly tender in the finished quiche.</li><li class="MethodStepper"><h4 class="step-title">Step 7</h4>In a large jug, whisk together the eggs, cream, milk, grated Gruyère (reserving a small handful for topping), nutmeg, salt and pepper. The consistency should be smooth and pourable – this custard base will set to a silky texture during baking.</li><li class="MethodStepper"><h4 class="step-title">Step 8</h4>Spread the onion and sage mixture over the base of the partially baked pastry case. Arrange about two-thirds of the sweet potato slices in overlapping layers on top of the onions. Carefully pour over the egg mixture, allowing it to seep between the layers. Arrange the remaining sweet potato slices decoratively on top, slightly pressing them into the custard. Scatter the whole sage leaves over the surface and sprinkle with the reserved cheese.</li><li class="MethodStepper"><h4 class="step-title">Step 9</h4>Bake in the preheated oven for 30-35 minutes until the filling is just set with a slight wobble in the center and the top is golden brown. The quiche continues cooking slightly from residual heat after removing from the oven, so it's better to slightly underbake than overbake.</li><li class="MethodStepper"><h4 class="step-title">Step 10</h4>Allow the quiche to rest for at least 15 minutes before removing from the tin – this resting period allows the custard to fully set and flavors to develop. Serve warm or at room temperature. The quiche can be made a day ahead and refrigerated; bring to room temperature or warm slightly before serving for the best flavor.</li></ol>