Caramelized Onion, Apple, and Gruyere Tart Recipe

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Want to know our #1 Thanksgiving appetizer??  This caramelized onion, apple, and gruyere tart!  The second it comes out of the oven our family gobbles it on up… we have to make double batches so people that arrive a few minutes late can have a bite!  I’m now sharing the recipe with you all because it is SO GOOD.  The secret is out!

Recipe for caramelized onion, apple, and gruyere tarts – printable recipe here

Ingredients:

• 2 Tbs. vegetable oil
• 1 1/2 lb. yellow onions, thinly sliced
• 1 tsp. kosher salt
• 2 Tbs. unsalted butter
• 1 lb. tart apples, peeled and sliced 1/8 inch thick
• 1 tsp. sugar
• 1 1/2 oz. Gruyère cheese, coarsely grated
• 2 Tbs. minced fresh chives
• 1 tsp. chopped fresh thyme
• 1/8 tsp. freshly ground pepper
• 1 package frozen puff pastry dough, thawed
• 1 egg, beaten with 2 Tbs. water

Directions:

In a large fry pan over medium heat, warm the oil. Add the onions and the salt and cook, stirring occasionally, until the onions are golden brown, about 30 minutes. Transfer to a large bowl and let the filling cool to room temperature.

Position 1 rack in the upper third and 1 rack in the lower third of an oven and preheat to 400°F. Line 2 baking sheets with parchment paper.

In the same pan over medium heat, melt the butter. Add the apples and sugar and stir to coat the apples. Cook, stirring, until the apples are just starting to caramelize and have softened, about 10 minutes. Transfer to the bowl with the onions and stir in the cheese, chives, thyme and the pepper.

Cut the puff pastry into 2-inch squares and place on the prepared baking sheets, spacing the squares about 1 inch apart. Brush the pastry squares with the egg mixture and place a heaping tablespoon of filling into the center of each square. Season lightly with additional salt and pepper.

Bake at 400F, rotating the baking sheets from top to bottom and front to back halfway through baking, until the pastry is crisp underneath and golden brown on top, about 25 minutes. Transfer the baking sheets to wire racks and let the tarts cool to room temperature. Serve at room temperature or warm. Makes 32 tarts.

Yes, the onions got a bit burned in the oven in the picture above but guess what – there were still no leftovers!