Directions
<ol class="no-list-style"><li class="MethodStepper"><h4 class="step-title">Step 1</h4>Start by making the pastry. Place the flour and salt in a large bowl and add the cold cubed butter. Using your fingertips, rub the butter into the flour until the mixture resembles breadcrumbs. The cold butter creates pockets of steam when baking, resulting in those gorgeous flaky layers we're after.</li><li class="MethodStepper"><h4 class="step-title">Step 2</h4>Gradually add the ice-cold water, a tablespoon at a time, mixing with a knife until the dough just comes together. Be careful not to overwork the dough or add too much water as this will make your pastry tough rather than tender. Form into a disc, wrap in cling film, and refrigerate for at least 30 minutes to relax the gluten.</li><li class="MethodStepper"><h4 class="step-title">Step 3</h4>While the pastry is chilling, prepare your mushrooms. Clean them gently with a damp cloth (avoid washing mushrooms if possible as they absorb water like sponges). Slice the mushrooms, keeping them relatively chunky for texture.</li><li class="MethodStepper"><h4 class="step-title">Step 4</h4>Heat the olive oil in a large frying pan over medium-high heat. Add the sliced onions with a pinch of salt and cook slowly for 8-10 minutes until soft and translucent. Add the garlic and cook for another minute until fragrant.</li><li class="MethodStepper"><h4 class="step-title">Step 5</h4>Increase the heat to high and add the mushrooms to the pan. It's important not to overcrowd the pan as this will cause the mushrooms to steam rather than caramelize. You might need to cook them in batches. Sauté until they release their moisture and then turn golden brown, about 7-8 minutes. The caramelization process creates rich umami flavors that are essential for a deeply flavored quiche.</li><li class="MethodStepper"><h4 class="step-title">Step 6</h4>Add the fresh thyme leaves to the mushrooms, season with salt and pepper, and cook for another minute. Remove from the heat and set aside to cool slightly. Preheat your oven to 190°C (170°C fan/375°F).</li><li class="MethodStepper"><h4 class="step-title">Step 7</h4>On a lightly floured surface, roll out your chilled pastry to about 3mm thickness, creating a circle large enough to line your tart tin with a little overhang. Carefully drape the pastry over your rolling pin to transfer it to the tin, pressing it gently into the corners. Don't stretch the pastry as it will shrink back during baking.</li><li class="MethodStepper"><h4 class="step-title">Step 8</h4>Prick the base all over with a fork to prevent air bubbles, then line with baking parchment and fill with baking beans or rice. Blind bake for 15 minutes, then remove the beans and parchment and bake for a further 5 minutes until the pastry is lightly golden. This crucial step ensures your pastry base stays crisp rather than soggy when you add the wet filling.</li><li class="MethodStepper"><h4 class="step-title">Step 9</h4>While the pastry is baking, prepare the custard filling. In a large bowl, whisk together the eggs, double cream, grated cheese, and nutmeg. Season with salt and pepper, remembering that the mushrooms and cheese already provide saltiness.</li><li class="MethodStepper"><h4 class="step-title">Step 10</h4>Once the pastry case is par-baked, trim any excess pastry from the edges for a neat finish. Spread the mushroom mixture evenly over the base of the pastry case. Carefully pour the eggy custard over the mushrooms, ensuring an even distribution. Sprinkle a little extra thyme on top if desired.</li><li class="MethodStepper"><h4 class="step-title">Step 11</h4>Lower the oven temperature to 180°C (160°C fan/350°F) and bake the quiche for 25-30 minutes until the filling is set but still has a slight wobble in the center. The custard will continue to cook slightly after removing from the oven, so don't be tempted to overbake or your quiche will become rubbery.</li><li class="MethodStepper"><h4 class="step-title">Step 12</h4>Allow the quiche to cool in the tin for 10-15 minutes before carefully removing. This resting time helps the custard to set fully and makes slicing cleaner. Serve warm or at room temperature, garnished with additional fresh thyme leaves. The quiche can be stored in the refrigerator for up to 3 days and reheated gently, or enjoyed cold.</li></ol>