
Gabriel Kreuther's Onion Tart. Credit: Gabriel Kreuther
My Onion Tart
FOR THE DOUGH
All purpose flour: 2 cup
Cold butter: 1 stick + 1 tbsp (diced)
Salt: to taste
Cold water: 1/3 cup
FOR THE FILLING
Onions: 3.5-4 lb
Salt: to taste
Applewood-smoked slab bacon: 4 oz (cut into thin strips)
Eggs: 4
Heavy cream: 1 cup
Milk: 3/4 cup + 2 tbsp
Parsley: 2 tbsp (chopped)
Pepper: 50 grinds or to taste
Nutmeg: 30 gratings or to taste
Gruyère cheese: 3 oz (or enough to sprinkle liberally over the tart)
(From Gabriel Kreuther: The Spirit of Alsace by Gabriel Kreuther with Michael Ruhlman. Copyright © 2021, published by Abrams. Reprinted and lightly edited by permission of Gabriel Kreuther.)
This is a highlight of Alsatian farm cuisine—a simple onion tart, with bacon and cheese. It’s like a thin quiche. It uses only the simplest ingredients but when properly cooked is a supreme dish. I intensify the traditional recipe by using a puree of steamed onions as part of the custard or flan for more onion flavor and sweetness. This was a regular feature of my childhood. My mother usually served it with a green or celeriac salad.
- In a mixing bowl, blend the flour, butter, and salt with your fingertips until the mixture resembles coarse meal with pea-sized lumps.
- Add most of the water and mix until the dough comes together. Add more water as needed.
- Knead until smooth and not sticky. Wrap in plastic and refrigerate for 30 minutes.
- Steam three-quarters of the onions for 1 hour or roast in foil at 350°F until tender.
- Puree the steamed/roasted onions in a blender until smooth.
- Thinly slice the remaining raw onions. Slice them by halving lengthwise, cutting through the center, and slicing thinly top to bottom.
- Place sliced onions in a bowl, toss with 1 teaspoon salt, and set aside.
- Preheat oven to 325°F.
- Roll out the rested dough and line an 11- or 12-inch tart pan. Poke holes with a fork.
- Cover with parchment or foil, add weights, and blind bake for 20 minutes.
- In a saucepan over medium heat, sauté the bacon until cooked and lightly browned but not crispy.
- Remove from heat and let cool in the pan.
- Increase oven temperature to 375°F.
- In a bowl, beat eggs and whisk in cream, milk, onion puree, sliced onion, salt, parsley, pepper, and nutmeg.
- Pour the mixture into the tart shell.
- Sprinkle grated Gruyère over the top.
- Distribute the bacon evenly over the tart. Optionally, drizzle with rendered bacon fat.
- Bake for about 40 minutes, until just set (it should jiggle but not appear liquidy).
- Cool for 15 minutes before serving warm, or let cool completely to serve at room temperature.
- The tart keeps well in the fridge for several days.