Caramelized Onion Crepes

Heat the oven to 375°F. Trim, peel, and halve the onion; slice it into half moons. Put 1 tablespoon oil in a large skillet over high heat. When it’s hot, add the onions, spread them out evenly, and cook, undisturbed, until they darken on the bottom, 2 or 3 minutes. Sprinkle the onions generously with salt, stir, and lower the heat to medium; continue to cook, stirring occasionally until they’re soft, 5 to 10 minutes. Add 2 tablespoons of the wine or water and cook, scraping up any browned bits from the bottom of the pan, until almost all the liquid has evaporated, 1 or 2 minutes more.

Grease a rimmed baking sheet with 1 tablespoon oil. Wet your hands and pat the tortillas with a generous amount of water on both sides. Put the tortillas on the prepared pan (it’s okay if one side of each tortilla overhangs) and divide the onions between them. Working with one tortilla at a time, spread the filling over half the tortilla in a semicircle, and then fold it in half twice, forming a quarter circle; repeat with the remaining tortilla. Cover the baking sheet tightly with foil and bake until heated through, 7 to 10 minutes.

Rinse, trim, and quarter the mushrooms. Wipe out the skillet, add the remaining 2 tablespoons oil, and put it over medium-high heat. When it’s hot, add the mushrooms, sprinkle with salt and pepper, and cook, stirring occasionally until they begin to color, 3 to 5 minutes. Add 2 tablespoons wine or water and cook until most of the liquid has evaporated, 1 to 3 minutes. Lower the heat to medium and cook until the mushrooms are tender, 3 to 5 minutes more.

Rinse and trim the spinach; shake it dry. Put a pile of spinach on top of the mushrooms, drizzle with the vinegar, and cook, tossing and adding more spinach as you have room (you may not need it all), until it’s wilted, 3 to 5 minutes. Taste and adjust the seasoning. Serve each crepe topped with the mushrooms and spinach.