Speck and Caramelized Onion Flammkuchen with Oat Crème Fraîche

A gorgeous Alsatian-style flatbread from the border region of France and Germany, topped with a tangy oat-based crème fraîche base, sweet slow-cooked caramelized onions, and smoky, salty speck. The crust is paper-thin and crisp at the edges, tender in the middle — basically the original pizza, and wildly impressive for how simple it is. We're baking this on your cast iron pan for that perfect rustic char. Completely free of all dairy — cow and goat alike — thanks to oat-based crème fraîche and cream cheese that bring that same luscious tang.

Ingredients

  • 3 cups All-purpose flour, plus extra for dusting
  • 1 tsp Instant dry yeast
  • 1 tsp Salt
  • ¾ cup + 2 tbsp Warm water
  • 2 tbsp Olive oil
  • 2 tbsp Margarine
  • 4 large Large yellow onions, halved and thinly sliced into half-moons
  • 3 tbsp Dry white wine
  • 1¼ cups Oat crème fraîche
  • 3 oz Oat cream cheese, at room temperature
  • ¼ tsp Nutmeg, freshly grated if possible
  • to taste Fine sea salt
  • 7 oz Speck, thinly sliced
  • ¼ cup Fresh chives, finely snipped
  • 1 tbsp Olive oil

Instructions

  1. Make the dough: In a large bowl (or in your food processor with the dough blade), combine 3 cups (360 g) all-purpose flour, 1 tsp instant dry yeast, and 1 tsp salt. Give it a quick mix. Add ¾ cup + 2 tbsp (210 ml) warm water and 2 tbsp (30 ml) olive oil. Mix with a fork until a shaggy dough forms, then turn it out onto a lightly floured surface and knead for about 5 minutes until smooth and elastic — or pulse in the food processor for 60 seconds. The dough should be soft but not sticky. Shape into a ball, place back in the bowl, cover with a damp cloth, and set aside to rest.
  2. Start the caramelized onions — this is the long game and where all the magic happens. Place a large heavy-bottomed pan (or your cast iron pan) over medium-low heat and melt 2 tbsp (28 g) margarine. Add all the thinly sliced onions and a pinch of salt. Stir to coat. Let them cook low and slow.
  3. Cook the onions, stirring every 4–5 minutes, for about 40–45 minutes total until they are deeply golden, jammy, and sweet. Don't rush this — low and slow is the only way. If they start to stick, add a splash of water and scrape up any fond. At the 40-minute mark, pour in 3 tbsp (45 ml) dry white wine, stir well, and let it bubble and absorb for 2 minutes. Remove from heat and set aside.
  4. While the onions are caramelizing (around the 20-minute mark), prepare the oat crème fraîche base. In a bowl, use a fork or small whisk to beat together 1¼ cups (300 ml) oat crème fraîche, 3 oz (85 g) room-temperature oat cream cheese, ¼ tsp freshly grated nutmeg, and a good pinch of fine sea salt until smooth and spreadable. Oat cream cheese can be a little firmer, so take a moment to make sure it's fully incorporated — no lumps. Taste and adjust salt. Cover and refrigerate until needed.
  5. Preheat your oven to 500°F (260°C) — as hot as it will go. If you have a convection setting, use it. Place your cast iron pan inside the oven to preheat as well — a blazing-hot surface is the key to that trademark crispy base.
  6. Divide the rested dough into 2 equal pieces (you'll bake two flammkuchen in batches). On a lightly floured surface, roll the first dough piece out as thin as you possibly can — aim for about 3 mm (⅛ inch) thick, roughly the shape of your cast iron pan or a large oval. It should be almost translucent in places. Traditional flammkuchen is THIN — that's the whole point!
  7. Carefully remove the scorching-hot cast iron pan from the oven using thick oven mitts. Brush it lightly with ½ tbsp (7 ml) olive oil. Quickly drape the rolled dough over the pan and press it gently to fit. Work fast — the dough will start crisping immediately on contact, and that is exactly what you want.
  8. Spread half the oat crème fraîche mixture over the dough, leaving a bare 1 cm (½ inch) border around the edge. Top with half the caramelized onions, spreading them evenly. Lay half the thinly sliced speck across the top in a loose, overlapping pattern.
  9. Bake in the 500°F (260°C) oven for 10–12 minutes, until the edges are deeply golden and charred in spots, the oat crème fraîche is bubbling and lightly set, and the speck is crisping up beautifully. Keep an eye on it — ovens vary at this temperature. Note that oat-based crème fraîche may not brown quite as deeply as dairy, but it will bubble and set into a gorgeous creamy layer.
  10. While the first flammkuchen bakes, roll out the second dough piece and have your toppings ready to go so you can get it straight into the pan the moment the first one comes out.
  11. Remove the first flammkuchen from the oven. Scatter half the snipped fresh chives over the top. Slide it onto a board and cut into irregular shards or strips — no need for neat squares, rustic is the vibe. Repeat the process for the second flammkuchen: brush the pan with the remaining ½ tbsp olive oil, drape the dough, top, and bake for another 10–12 minutes.
  12. Scatter the remaining fresh chives over the second flammkuchen. Serve both immediately while they're hot and crisp — flammkuchen waits for no one!