Caramelized Onion, Apple & Gruyère Quiche

Caramelized Onion, Apple & Gruyère Quiche

Yield: 1 (9-inch or 10-inch) quiche (6–8 slices)

Prep Time: 25 minutes

Cook Time: 1 hour 10 minutes

Ingredients

For the Crust:

  • 1 pre-made or homemade single pie crust (chilled)

For the Filling:

  • 2 large yellow onions, thinly sliced

  • 1 large Honeycrisp or Gala apple, cored and thinly sliced

  • 2 tbsp unsalted butter

  • 1 tbsp olive oil

  • 1 tbsp fresh thyme leaves (plus a few sprigs for garnish)

  • 1 tsp brown sugar

  • 1 tbsp apple cider vinegar (or white wine)

  • Pinch of ground nutmeg

  • 4 large eggs

  • 1 cup heavy cream

  • ½ cup whole milk

  • 1 cup (approx. 4 oz) Gruyère cheese, freshly shredded

  • ½ tsp kosher salt

  • ¼ tsp freshly cracked black pepper

Instructions

1. Blind Bake the Crust

  1. Preheat oven to 400°F (200°C).

  2. Line your pie dish with the pie dough, crimping or fluting the edges nicely around the rim. Dock the bottom all over with a fork.

  3. Line the dough with parchment paper and fill with pie weights or dried beans.

  4. Bake for 15 minutes, then carefully remove the weights and parchment. Bake for an additional 5 minutes until the bottom is pale gold and set.

  5. Remove from oven and reduce oven temperature to 350°F (175°C).

2. Caramelize the Onions & Apples

  1. In a large skillet over medium heat, melt the 2 tbsp butter with 1 tbsp olive oil.

  2. Add the sliced onions, 1 tsp brown sugar, and a pinch of salt. Cook low and slow for about 20–25 minutes, stirring occasionally, until dark golden brown and sweet.

  3. Stir in the apple cider vinegar to deglaze the skillet, scraping up any browned bits.

  4. Add the thinly sliced apples and fresh thyme into the skillet with the onions. Sauté for another 4–5 minutes just until the apples soften slightly. Remove from heat and set aside to cool for a few minutes.

3. Assemble & Whisk the Custard

  1. In a medium bowl, whisk together the 4 eggs, 1 cup heavy cream, ½ cup milk, ½ tsp salt, ¼ tsp black pepper, and a pinch of nutmeg until completely smooth.

  2. Layer half of the shredded Gruyère onto the bottom of the par-baked crust.

  3. Spread the caramelized onion and apple mixture evenly over the cheese.

  4. Top with the remaining shredded Gruyère.

  5. Slowly pour the egg custard mixture over the fillings, filling up to just below the fluted rim.

4. Bake & Serve

  1. Transfer the pie dish to the middle rack of your oven (you can place it on a rimmed baking sheet for easy handling).

  2. Bake at 350°F (175°C) for 35–45 minutes, or until the custard is set around the edges with a very slight, gentle wobble in the center.

  3. Transfer to a wire rack and let cool for at least 20–30 minutes before slicing to allow the custard to set properly.