makes 1 tart, serves 6–8; adapted from Nick Malgieri and Jennifer Millar
Sprinkle yeast over the lukewarm water in a mixing bowl and let stand until yeast is dissolved. Mix in the egg, olive oil, salt and spelt flour. Scrape the dough onto a floured surface and knead for a couple minutes. Shape into a ball and cover with plastic wrap for 20 minutes before rolling.
Preheat oven to 425°F. Lightly grease the interior bottom and sides of pan with butter or nonstick spray.
Rinse greens in a large bowl of water; lift out and roll up in a clean kitchen towel to absorb excess water. Remove central rib stem from each leaf, stack together and finely chop, set aside. Stack the leaves, roll them up, and cut across every inch into ribbons (chiffonade).
Heat olive oil in a large frying pan over medium heat. Add onions and the chopped stems and cook until softened, about 5 minutes. Add garlic and greens and cook until wilted, another 5 minutes. Remove from heat and set aside to cool as you roll out the pastry.
On a lightly floured surface, roll out the pastry into a large, thin circle, approximately 14-inches in diameter. Dust the top with a bit of spelt flour and rollup onto your rolling pin, transfer to your prepared pan and ease the pastry down to line the bottom and sides, allowing excess to drape over edge.
Press and drain off as much liquid as possible from the wilted greens, then turn out onto cutting board and roughly chop. Crack the eggs into a mixing bowl and whisk in the ricotta. Add ¾ cup Parmesan, the chopped greens, salt, and pepper. Mix to combine and pour into the pastry-lined pan. Sprinkle top with remaining ¼ cup Parmesan and fold pastry edges towards center.
Bake at 425°F for 15 minutes then lower oven temperature to 375° and continue baking until filling is set and top begins to brown, about 20–25 minutes more. Let cool at least 10 minutes before slicing. Store any leftovers in the refrigerator and enjoy chilled, room temperature, or reheated in a warm oven.