Home, Cooking: Five-Onion Tart, With or Without Bacon

As a lifelong Onion, I’m only mildly triggered by the inclusion in this savory tart’s ingredients list of all the alliums kids used to stick into jokes about my name in elementary school. (“Becky Garlic!” “Scallion, you make me cry!”) 

I don’t know why this joshing bothered me so much—now, the jibes seem mild as a caramelized shallot—but kids don’t like being associated with anything that stands out, especially a thing that smells. I wished for any other food name, jealous of my camp friend Ben Fried and the singer Fiona Apple, neither of whom knew how easy they had it. 

Thankfully, these days I love my name, and around holiday times, I feel particularly sentimental about this tart. I stretch the truth a bit for the name (garlic is not an onion!), because there were five Onions in my family of origin. One of them (who lives near Stonewall Kitchen HQ, in Maine) gave me the cookbook with the original version of this recipe in it. 

This tart, full of cream and butter, is the perfect antidote to the cold weather we’re about to have. If you can slide this one onto a December party buffet, do — or save it for New Year’s Eve. 

Five-Onion Tart, With Or Without Bacon (adapted from Stonewall Kitchen Harvest) 

Ingredients: 

For the pastry: 

2 cups all -purpose flour

Pinch salt

I tablespoon chopped fresh thyme, or teaspoon dried

1 cup (2 sticks) unsalted butter, cut into cubes, cold from the fridge or freezer 

¼ cup ice water, or as needed 

For the filling: 

4 strips thick, country-style bacon (optional) 

2 tablespoons olive oil, or 1 tablespoon olive oil and 1 tablespoon garlic oil 

I medium onion, very thinly sliced

½ pound leeks (about 3 thin leeks, or 1 to 2 medium-large, white part only), cut in half lengthwise, rinsed, and thinly sliced 

1 large shallot, very thinly sliced

2 small garlic cloves, very thinly sliced

2 scallions (white and green parts), trimmed and chopped

1 teaspoon unsalted butter

1 tablespoon chopped fresh thyme, or ½2 teaspoon dried

Salt and freshly ground black pepper to taste

1 cup heavy cream

1 cup freshly grated Parmesan or Gruyère cheese (or, half and half) 

Equipment: 

The cookbook recommends a rectangular, 13¾” x 4½” x 1″ tart pan (like this one). I bought one for the purposes of this recipe, long ago, and when I use it, the tart does indeed look great. But you can also use a much more commonly available 9-inch tart pan, with a removable bottom. 

Directions: 

1. First, the pastry. Put the flour, salt, and thyme in the bowl of a food processor. Add the butter cubes. Pulse until what’s in the bowl looks rubbly (the original recipe described the desired texture as “coarse cornmeal”). Add ¼ cup water, and pulse a few times, until the dough starts to coalesce. Add more water if it’s not happening. Then, lay some plastic wrap out on the counter. Turn out the dough onto the wrap and gather it all together into a ball. Put the ball in a Pyrex or tupperware to avoid getting crumbs all over your fridge by mistake. Refrigerate at least two hours. (You can do this a day or two before you intend to make the tart—or freeze even further ahead of time.) 

2. In the meantime, the filling. If you’re using bacon (this tart will still be great without it), cook it until it’s crisp, medium heat, 5 to 8 minutes. Drain on paper towels and let cool, then crumble into ½-inch pieces. (You can do this ahead and save the bacon in the fridge for a day or two.) 

3. Meanwhile, heat 1 tablespoon oil over low heat in a large skillet. Add the onion, and cook for 5 to 10 minutes, stirring often. Add the rest of the alliums (leeks, shallot, garlic, scallions), the butter, and half the thyme, and season with salt and pepper. Now you’re caramelizing! Cook over very low heat, for 15 minutes, or longer if you have the time, until it looks as brown as you can get it. (You could also do the onion mix ahead and put it in the fridge for a day or two.) 

4. Now, make the tart. Set the oven to 350. Get a skillet going with the cream and thyme in it, and put it at low heat. Simmer for 5 to 8 minutes, allowing the wide surface area of the skillet to cook down the cream, until it’s thick at the edges. 

5.  While that’s simmering, flour your counter, get the dough out of the fridge, and roll it out into a rectangle (if you’re using a rectangular tart pan) or a circle (for a more typical circular pan). Pick up the dough and drape it in the pan. (If the dough is breaking up, as it always does for me — what is my problem? — you can also put it into the pan when it’s in clumps and use your fingers to spread it into the pan and up the sides. This will still taste good.) 

6. Add the cream to the onion mixture, add the bacon (if using) and the grated cheese, and pour it all into the prepared crust. Smooth the mix to the edges of the pan. 

1. Place this whole shebang on a cookie sheet and bake in the middle of the oven, for about 1 hour. You want it to be a beautiful golden brown — not too dark — so check it at the 30 or 40 minute mark to see if it’s overbrowning. If it is, cover it with a sheet of foil, and set the oven at 325 degrees for the rest of the hour.