My troubles started when I had it in my mind that this Alsatian specialty was made of a very thin pizza dough crust, spread with fromage blanc (a soft, white cheese), then topped with bacon and caramelized onions and baked.
I don’t know where the caramelized onion idea came in. The thing about France I’ve found again and again is that not only is there never one recipe for any classic, but there’s not always a consensus on exactly what the classic is (unless there’s an Acadamie Française of cuisine that I don’t know of). Somewhere in my travels, I’ve had the treat with caramelized onions.
When I tried to make it with caramelized onions at home, it was a drab, brown thing, and didn’t taste much better than it looked. Further research revealed that the onions are not cooked, but rather sliced super thin—so thin that they will roast and mellow somewhat as they bake at a high temperature atop the tart.
Onion problem solved. But what on earth was that creamy layer? Crème fraîche or fromage blanc? And could I use the more easily found Fage Greek Yogurt, which, uncooked, somewhat resembles Fromage Blanc?
My cookbook is all about finding widely available stand-ins for less-common French products, but the stand-ins have to work beautifully or they’re out. I tried the Greek-style yogurt. No dice. The yogurt baked to a weird consistency (like semi-melted plastic) that glided off the partially baked crust.
When I was at the market looking for fromage blanc, I ran into local chef, David Baruthio, whose restaurant, Baru 66, is in the running for Best New Restaurant this year from the James Beard Foundation. Because he’s from Strasbourg, the capital of Alsace, I thought he might know a thing or two about Tarte Flambée.
First of all, he said, you can use either crème fraîche or fromage blanc, or both, but crème fraîche was better. He mentioned that some cooks thicken the crème fraîche with flour before spreading it on the crust. And the crust? Traditionally, it’s not a pizza crust at all, but a thin, unleaven crust.
Sadly, the market only carried nonfat fromage blanc. I wanted to test with the regular version. My only option was to go clear across town to Trader Joe’s find it.
And friends, the promise of my book is that you shouldn’t have to drive across town for fancy ingredients for any of my recipes. Doing so is not in the spirit of everyday French home cooking. So I bought the crème fraîche and headed home.
Here’s another issue I came across: Most French recipes for Tarte Flambée call for oven temperatures of 500°F or more (after all, flamber means to set afire). I don’t think we literally want to set this tart on fire in the home kitchen. And I don’t know about your oven, but in mine, there’s usually some residue left over from another baking project that’s going to start smoking at that high heat, and set off my fire alarm. For me, 450°F is as high as I go.
I won’t go into the details of how many times I tested the crust at different temperatures and timings. But in the end, instead of using an unleaven crust, I used a basic recipe for pizza dough—but I didn’t let it rise very much. It bakes well at the 450°F. It’s flat but nicely chewy, very easy and quite good.
Back to the crème fraîche. I made the recipe with this French-style sour cream. Alas, the crème fraîche ran over the sides of the tart and melted until it was quite liquidy. A messy tart (but it tasted good).
I thought of Baruthio’s suggestion of adding flour to the crème fraîche, and I also saw another recipe that added an egg. So, on about the eighth attempt at making this tart, I topped half of it with a mixture of flour/sour cream and another half with a mixture of egg/sour cream.
Both worked well, but I give the egg version the edge. The flour/sour cream side brought a nicely thickened layer of sour cream, while the egg/sour cream version had a slightly custardy richness that I loved. The tanginess of the sour cream, the sweet-hotness of the onions, the salty-smoky flavor of the bacon—finally, it was all working beautifully together.
And why sour cream? Crème fraîche is expensive and not that widely available. Sour cream, once you mix it with the egg, becomes rich and wonderful and just fine for this tart. Especially since there are other great flavors at work here, too.
What next? I’m going to test the recipe one more time. If anyone out there wants to test it, too, I’d be eternally grateful.
And thanks. I’m sure that the only people who have got to the end of this post are true recipe geeks. I appreciate your interest, and any suggestions you have with this tart.
Alsatian Bacon and Caramelized Onion Tart (So Far)
Makes 8 appetizer or side-dish servings
1/2 recipe Pizza Dough
6 slices bacon (about 3 ounces)
1 medium onion
1 cup sour cream
1 large egg, beaten
Position an oven rack to lowest position. Grease one large rimmed baking sheet. Preheat oven to 450°F. Prepare pizza dough as directed through step two, reserving one ball of dough for later use (refrigerate for up to 3 days). Roll the remaining ball into a 10-inch round on the sheet; roll edges over once to form a rim. Set aside.
Cook bacon in a large skillet over medium heat until cooked but not crisp. Drain on paper towels, then cut into 1/2–inch pieces. Using a small, sharp knife, slice the onion in half, then slice each half as thinly as you can (you should almost be able to see through the slices). Separate the slices into half-rings (you should have about 1 cup); set aside. In a small bowl, beat the sour cream and egg together until smooth. Set aside.
Prick dough all over with a fork. Bake on lowest oven rack for 5 minutes. Remove from oven; flatten any air bubbles with a fork.
Spread the sour cream and egg mixture atop the partially baked crust. Top onions and bacon. Sprinkle with salt and freshly ground black pepper to taste.
Bake until crust is golden brown on bottom and edges, about 10 to 12 minutes more. Let cool on wire rack for five minutes before cutting into 8 pieces to serve.