Culinary Curious

French Onion and Bacon Tart From America's Test Kitchen Season 10: Egg Dishes with an Accent

French Onion and Bacon Tart

Presented by America's Test Kitchen

WHY THIS RECIPE WORKS:


French onion tart is similar to quiche but delivers a more refined slice of pie, with more onions than custard. But re-creating this tart at home can produce a tough and crackery crust, which is doubly disappointing after spending long hours delicately cooking the onions, making the custard, and baking the whole thing together. We wanted to simplify the crust and shorten the overall preparation time.

We found that our onions would cook in half the usual time if we left the lid on the skillet throughout cooking. And covering the onions allowed them to cook entirely in their own juices, thereby becoming tender, retaining their pure onion flavor, and cooking more evenly. We liked bacon, which acted as a crisp foil to the creamy filling, but we found a traditional custard with the bacon to be simply too rich. To resolve the issue, we reduced the number of eggs and switched out the cream for half-and-half. And to ensure the bacon stayed crisp, we sprinkled it on top of the custard. We tried several classic crust recipes, looking for one that had the intense butteriness of traditional tart dough but could still be easily patted into a tart pan. We found that using a food processor to cut cold butter completely into the flour mixture required less ice water than a conventional crust, which kept the dough firm enough to press into the pan.

SERVES 6-8

Either yellow or white onions work well in this recipe, but stay away from sweet onions, such as Vidalias, which will make the tart watery. Use a 9-inch tinned-steel tart pan. This tart can be served hot or at room temperature and pairs well with a green salad as a main course. Leftovers should be wrapped in plastic wrap and refrigerated. Reheat on a baking sheet in a 325-degree oven for 10 to 15 minutes.

Ingredients

Crust

  • 1 ¼ cups unbleached all-purpose flour (6 ¼ ounces)
  • 1 tablespoon sugar
  • ½ teaspoon table salt
  • 8 tablespoons unsalted butter (1 stick), cut into 1/2-inch cubes and well chilled
  • 2 - 3tablespoons ice water

Filling

  • 4 ounces bacon (about 4 slices), halved lengthwise, then cut crosswise into 1/4-inch pieces
  • Vegetable oil, if needed
  • 1 ½ pounds onions, halved through root end, peeled, and cut crosswise into 1/4-inch slices (about 6 cups), see photo below
  • 1 sprig fresh thyme
  • ¾ teaspoon table salt
  • 2 large eggs
  • ½ cup half-and-half
  • ¼ teaspoon ground black pepper

INSTRUCTIONS

  1. FOR THE CRUST: Spray 9-inch tart pan with nonstick cooking spray. Combine flour, sugar, and salt in food processor with four 1-second pulses. Scatter butter pieces over flour mixture; pulse to cut butter into flour until mixture resembles coarse sand, about fifteen 1-second pulses. Add 2 tablespoons ice water and process until large clumps form and no powdery bits remain, about 5 seconds, adding up to 1 tablespoon more water if dough will not form clumps. Transfer dough to greased tart pan. Following illustrations above, pat dough into prepared pan. Lay plastic wrap over dough and smooth out any bumps or shallow areas. Place tart shell on plate and transfer to freezer for 30 minutes.
  2. Adjust oven rack to middle position and heat oven to 375 degrees. Place frozen tart shell on baking sheet; lightly spray one side of 18-inch square extra-wide heavy-duty aluminum foil with nonstick cooking spray. Press foil greased side down inside tart shell, folding excess foil over edge of pan. Fill with pie weights and bake until top edge just starts to color and surface of dough under foil no longer looks wet, about 30 minutes. Remove from oven and carefully remove foil and weights by gathering edges of foil and pulling up and out. Return baking sheet with tart shell to oven and bake until golden brown, 5 to 10 minutes. Set baking sheet with tart shell on wire rack. Do not turn off oven.
  3. FOR THE FILLING: While crust is baking, cook bacon in 12-inch nonstick skillet over medium heat until browned and crisp, 8 to 10 minutes. Drain bacon through mesh strainer set over small bowl; transfer bacon to paper towel-lined plate. Return 2 tablespoons bacon fat to skillet, adding vegetable oil to make up difference if necessary.
  4. Add onions, salt, and thyme to skillet. Cover and cook until onions release liquid and start to wilt, about 10 minutes. Reduce heat to low and continue to cook, covered, until onions are very soft, about 20 minutes, stirring once or twice (if after 15 minutes onions look wet, remove lid and continue to cook another 5 minutes). Remove pan from heat and let onions cool 5 minutes.
  5. Whisk eggs, half-and-half, and pepper together in large bowl. Remove thyme sprig from onions; discard. Stir onions into egg mixture until just incorporated. Spread onion mixture over baked crust (still on baking sheet) and sprinkle bacon evenly on top.
  6. Return baking sheet with tart to oven and bake until center of tart feels firm to touch, 20 to 25 minutes. Cool on wire rack at least 10 minutes. When ready to serve, remove tart pan ring; gently slide thin-bladed spatula between tart pan bottom and crust to loosen, then slide tart to serving plate. Cut into wedges and serve.