Friday, September 2, 2011

Caramelized Onion, Mushroom & Gruyere Tartlets

Every once in a while you stumble upon a culinary trick that changes your life in the kitchen — the magic of puff pastry. Considered by many to be the Queen of Pastry, making it from scratch can be laborious and unforgiving, even for professionals. So why bother, when there are so many pre-made brands from which to choose. I always like to keep a stock of puff pastry in the freezer so that I can make any number of delectable sweet or savoury dishes in no time at all — from galettes, tarts, turnovers, sausage rolls and even savoury cheese straws which I curl and twist from any left over scraps. 

There's an elegant beauty to puff pastry — the way its paper-thin layers puff like magic, delicately crisp and golden. The way it shatters with each bite. The deep buttery richness tucked inside every morsel. These delicious little Caramelized Onion, Mushroom and Gruyere tartlets are gloriously rich and delicious, and best of all, they're easy to make. Finely chopped onion, sautéed in a little butter until it caramelizes, is added to sliced mushrooms, garlic and thyme, and cooked until all the liquid evaporates. This savoury mixture is then spooned on top of little coin-size discs of puff pastry and sprinkled with gruyere cheese. Baked for about 15 minutes, these gorgeous fragrant savoury tartlets come out of the oven, bubbling, golden brown and absolutely delicious — a perfect appetizer for any party!

Caramelized Onion, Mushroom & Gruyere Tartlets
Makes about 12 2-inch appetizers

1 tbsp olive oil
1 small yellow onion, finely chopped
1 tbsp unsalted butter

8 oz white button mushrooms, thinly sliced

1 clove garlic, chopped

½ tsp dried thyme

Salt and pepper, to taste

¼ cup white wine
1 sheet puff pastry
1 cup shredded Gruyere or Swiss cheese
1 egg and 1 tbsp water, beaten together, for the egg wash
parsley or onion sprouts, for garnish

Preheat oven to 375°F and line a baking sheet with parchment paper. Heat the olive oil in a wide, heavy-bottomed pan over medium-low heat and add the onions. Cook, stirring occasionally, until they begin to caramelize, about 20 minutes. Add the butter to the pan. Once melted, add the mushrooms and sauté, stirring occasionally, until they are completely soft and all of the liquid evaporates, about 20 minutes. Add the garlic and the thyme and saute until fragrant, about 1 minute. Season with salt and pepper to taste. Add the wine, scraping the bottom of the pan to pull up all of the browned bits, and cook until all of the liquid has evaporated. Remove from heat.

Unfold the thawed sheet of puff pastry and cut out 2-inch circles from the dough, placing them evenly spaced on the baking sheet. Using a very sharp knife, make a score around the diameter of the dough, about ¼-inch from the edge. Top the rounds of puff pastry with a small spoonful of the onion and mushroom mixture, trying to keep the filling within the score marks. Top with the shredded Gruyere cheese. Brush the edges of the dough rounds with the egg wash, and bake until the pastry is golden brown, about 15 to 20 minutes. Serve warm and garnish with fresh chopped parsley or onion sprouts.