Low Histamine Caramelized Onion Tart
Slow-cooked onions are genuinely one of the most rewarding things you can make in a home kitchen, and this tart lets them take center stage in the most satisfying way. Three pounds of yellow onions get coaxed down into a deeply golden, jammy layer over nearly an hour of patient stirring — the kind of low-and-slow cooking that fills your kitchen with an almost sweet, savory perfume. A splash of apple cider vinegar and fresh thyme go in right at the end, brightening the whole thing without overwhelming the mellow, caramelized base. The olive oil crust comes together without any fuss and bakes up crisp and golden, giving you a sturdy, flaky foundation that holds every bit of that luscious topping. Fresh cow's milk mozzarella melts gently over the onions, staying mild and creamy rather than sharp or aged — an important distinction when you're keeping histamine in check, since fresh mozzarella is a far friendlier choice than aged or fermented cheeses. The whole tart slices cleanly after a short rest and serves eight, making it a genuinely impressive option for a crowd without requiring any complicated sourcing or substitutions. A handful of fresh parsley scattered over the top adds a clean, herby finish that ties everything together beautifully.
About FigFig is a food discovery app that helps you find foods and recipes that fit your dietary needs. Whether you have food allergies, intolerances, or follow a specific diet, Fig makes it easy to eat with confidence.
Learn more →Ingredients
8 servings
For the crust
- 2 cups all-purpose flour
- ½ tsp fine salt
- ½ cup olive oil
- ¼ cup cold water
For the topping
- 3 lb yellow onions (about 6 medium), thinly sliced
- 3 tbsp olive oil
- ½ tsp fine salt
- 1 tbsp apple cider vinegar
- 1 tbsp fresh thyme leaves
- 4 oz fresh cow's milk mozzarella (fior di latte), thinly sliced
For serving
- ¼ cup fresh flat-leaf parsley, roughly chopped (optional)
Instructions
- 1
In a large mixing bowl, whisk together the flour and salt. Add the olive oil and stir with a fork until the mixture resembles coarse crumbs. Drizzle in the cold water, 1 tablespoon at a time, stirring after each addition, until the dough just comes together and holds when pressed — it should not be sticky. Flatten into a disk, wrap in plastic wrap, and rest at room temperature for 30 minutes.
- 2
While the dough rests, heat 3 tablespoons of olive oil in a large skillet over medium heat until shimmering. Add the sliced onions and salt, toss to coat, and cook, stirring every 5 minutes, until the onions are completely softened and translucent, about 20 minutes.
Want the full recipe?
Create a Fig account for step-by-step instructions, access to our full recipe library, and more!