This dish is the French interpretation of Imam bayildi, a traditional Turkish stuffed eggplant. To me, it’s the best of both worlds. One thing I love about this tart is that the “crust” is simply made of onions: there’s no rolling or weighing involved. The layered vegetables are gloriously caramelized, not to mention just as pretty as a more traditional tart.
It helps to know: This recipe requires an 8- to 9-inch baking dish.
If you don’t have a dish that large, you can use two small pie pans or halve the recipe.
To make the “tart,” in a large pan on medium heat, stir together the olive oil, onions, garlic, and thyme.
Cook, stirring occasionally, until the onions are soft and lightly caramelized, about 20 minutes.
Set aside to cool to room temperature.
Preheat your oven to 375°F.
Spread the onion mixture over the bottom of your baking dish to form a “crust.
” Layer the tomatoes, zucchini, and eggplant in a cascading circle on top of the onions.
Alternate between the vegetables starting at the outside and working your way to the center.
It can be as pretty or as haphazard as you want, as long as the vegetables remain in one layer.
Drizzle the surface with olive oil, top with a couple large pinches of salt, and bake until the top is nicely browned and caramelized, about 45 minutes.
Meanwhile, to make the mayo, lightly toast the saffron in a small, dry pan on medium heat, shaking the pan until the saffron becomes fragrant and starts to lightly brown, about 1 minute.
Remove the pan from the heat and add 2 tablespoons water.
The pan will sizzle and the water will turn a vibrant orange.
Let cool to room temperature, then whisk the saffron water into your mayo, and stir in lemon juice to taste.
Remove the dish from your oven and let cool to room temperature.
Top with the grated Parmigiano-Reggiano and carve into slices like a pie.
Serve the slices on their own or with the saffron mayo on the side.