Serves 4 as a starter and 2 as a main
4 ounces (110g) sliced applewood-smoked bacon
3 large yellow onions (about 12 ounces/340g each)
1⁄2 cup (120ml) heavy cream
1 large egg yolk
2 tablespoons unsalted butter
Fine sea salt and freshly ground black pepper
2 tablespoons freshly grated Parmesan cheese, plus extra for sprinkling
Stack the slices of bacon, wrap in plastic wrap, and place in the freezer to firm. This will make them easier to cut.
To cut the onions using a meat slicer, cut off the root end of each onion and discard. Then cut off the other ends. With a paring knife, core each onion by cutting a cone-shaped piece from the root end of the onion, much as you would remove the stem of an apple. Stand each onion on one end and cut a vertical slit from top to bottom, just reaching the centre. This will result in long strands of onion rather than rings when the onion is sliced. Set the slicer to cut 1⁄8-inch (3mm) slices. Place a flat end of an onion against the blade and slice. Alternatively, to cut by hand (as pictured on pages 116–17), leave the root ends intact, but cut a slit in each onion as above, then cut across the onions to make 1⁄8-inch (3mm) slices. Separate the onion slices into strands. Place the longer strands in a bowl and reserve the shorter ones for another use. You should have about 8 cups (1.9L) loosely packed onions.
Place a steamer basket in a pot over simmering water. Place the onion strands in the basket, cover, and steam for 5 to 10 minutes, until the onions are translucent but still al dente. Taste one to make sure the sharp onion flavor has mellowed to your liking. Remove the basket from the pot. (This can be done a few hours before serving.)
Remove the bacon from the freezer, unwrap, and cut crosswise into 1/8-inch (3mm) strips. Put in a large nonstick skillet and sauté over medium-high heat, stirring often, for about 5 minutes, until crisp and browned.
Meanwhile in a small bowl, mix together 1/4 cup (60ml) of the cream and the egg yolk. Set aside.
Transfer the bacon to paper towels to drain. Pour out the fat and wipe the pan clean with a paper towel. Return the pan to the burner. Add the butter and melt over medium heat. Add the bacon and the remaining 1⁄4 cup (60ml) of cream and simmer for 30 seconds. Add the onions and 1⁄2 teaspoon each of salt and pepper. Toss and cook for 2 to 3 minutes, until the onions are hot. Remove the pan from the heat and stir in the reserved cream mixture and the Parmesan. Taste and add additional seasoning, if needed.
With a pair of tongs, lift each portion, letting excess sauce drip back into the pan, and arrange in small mounds on the serving plates. Serve sprinkled with additional Parmesan, if desired.
Excerpted from Food52 Genius Recipes: 100 Recipes That Will Change the Way You Cook by Kristen Miglore. Copyright © 2015 by Food52 Inc. Photographs copyright © 2015 by James Ransom. Published in the United States by Ten Speed Press, an imprint of the Crown Publishing Group, a division of Random House LLC, a Penguin Random House Company, New York. Reproduced by arrangement with the Publisher. All rights reserved.