Caramelized Onion Tart
This is a very simple side dish and perfect for a Sunday brunch or when you've had overnight guests. It keeps really well in the fridge if you have leftovers, and with temp-tations®, reheating is a breeze! - Tara
- 2 tablespoons olive oil
- 2 tablespoons unsalted butter
- 2 large onions, halved and cut into 1/4-inch half moons
- Kosher salt to taste
- 3 tablespoons thyme, plus 2 sprigs for garnish
- 1 sheet puff pastry, defrosted
- 1 egg white
- 1/2 cup grated Gruyère cheese
- Preheat oven to 400 degrees.
- In a large skillet over medium heat, combine olive oil and butter. When the butter has melted, add the onions and stir to coat. Spread the onions evenly to cover the bottom of the pan, cook 10 minutes, and then season with salt. Reduce heat if the onions begin to burn. Continue cooking until the onions are deep brown and lacquered, 30 minutes. Stir in the thyme.
- Meanwhile, generously flour a work surface and rolling pin. Roll the puff pastry out to a 9 ½ x 13-inch rectangle. Brush the pastry with the egg white. Using a very sharp knife, trim away 1-inch from each edge. Place the trimmed strips onto the pastry to create a raised rim. Transfer the pastry to a 4-quart temp-tations® dish.
- Using a fork, pierce the pastry all over the inside of crust and the raised rim. Bake until puffed and golden, 15 to 20 minutes. Scatter the Gruyère all over the tart. Spoon the onions over, covering the interior of the tart. Return to the oven and bake until the cheese melts, about 15 to 20 minutes. Garnish with the thyme and serve.