Step 1

Make the dough. In a large bowl, whisk together the egg, water, and salt. Begin gradually adding the flour (stop if the mixture is getting too dry) and stirring the mixture with a spoon – when it gets too thick, switch to your hands. Turn the dough out onto a lightly floured surface and knead it for about 5 minutes, making quarter-turns as you go. You should end up with a firm, elastic dough that doesn’t stick to your hands. If it’s sticky, add a bit more flour. Wrap the dough in plastic and refrigerate for 15-30 minutes.

Step 2

Preheat the oven on a low setting to keep the toppings warm later on, if desired. I personally don’t mind the onions and mushrooms at room temp.

Step 3

Make the toppings. In a large non-stick skillet, heat 1 tablespoon oil and 1 tablespoon butter over medium-low heat. Add the onions with 1/4 teaspoon salt and cook, stirring frequently, until they are soft and caramelized, about 20 minutes. Transfer to a bowl and set aside, or transfer to an oven-safe dish and keep warm in the oven.

Step 4

Add the remaining 2 tablespoons of oil to the skillet and increase the heat to medium. Add the mushrooms, cumin, 1/4 teaspoon salt, and pepper. Cook, stirring occasionally, until the mushrooms are nicely browned, about 7 minutes. Set aside.

Step 5

Bring a large pot of water to a boil.

Step 6

Remove the dough from the fridge and let it come to room temp while you make the sauce.

Step 7

Combine the yogurt, garlic, dill, and cilantro in a bowl. The sauce should be thick but pourable. Stir in a bit of water to achieve this consistency, if needed. Taste and season with salt.

Step 8

Cut the dough into 4 pieces and roll them into balls. Using a rolling pin, working with 1 ball at a time, roll out the dough to about a 1/16-inch thickness – it should be slightly thicker than pappardelle, as you want the noodles to have a chewy bite. Slice the dough into diamond-shaped noodles and transfer to a lightly floured baking sheet or tray. Repeat with the remaining dough.

Step 9

Season the boiling water generously with salt. Lower the noodles into the pot and stir gently to prevent them from sticking to the bottom. When they float up to the top and the water starts rapidly boiling again, they are done – this takes 2 minutes.

Step 10

Drain the noodles and transfer to a serving platter. Toss with the remaining tablespoon of butter and top with the onions and mushrooms. Sprinkle with sumac if using and black pepper. Serve immediately, with the yogurt sauce.