In Spain, tortillas are open-faced omelettes, usually made with potatoes and onions. They make an easy casual supper, a delicious breakfast or brunch offering, or great hors d’oeuvres.
Tortillas can be served hot or at room temperature. This vegetarian version is flavored with Indian spices; for a heartier dish, you can add diced ham, sausage, bacon or chicken. Using our heirloom fingerling potatoes, such as French Fingerling or Russian Banana, will make this dish extra tasty (though any potato will work). Leftovers reheat easily in a microwave or toaster oven.
Peel the potatoes and put them in a bowl of water as you go to keep them from turning brown. Drain, then place in a steamer over boiling water, cover and steam until just tender, about 15 to 18 minutes. Drain and set aside to cool; when they're cool enough to handle, cut them into 1/8-inch thick slices.
Meanwhile, heat the oil in a 9- or 10-inch skillet (preferably cast iron) over medium heat. Add the onion and half of the jalapeño and cook, stirring frequently, until the onion softens and colors, about 10 minutes. Add the garlic, curry powder, cumin and garam masala; cook, stirring constantly, for 1 to 2 minutes more. Remove the skillet from the heat. Being careful not to burn your fingers, neatly arrange the potatoes in the skillet in several layers, alternating with the tomatoes.
Whisk the eggs in a bowl, then stir in the minced cilantro. Add salt and pepper to taste. Pour the egg mixture gently into the skillet; avoid disturbing the potatoes. Return the skillet to the stove and cook over low heat until the egg is almost completely set, about 12 to 15 minutes.
Meanwhile, position an oven rack 7 or 8 inches from the broiler and preheat on high. Transfer the skillet to the oven and broil until the tortilla is puffed and golden brown, 2 to 5 minutes. Remove from the broiler and let the tortilla stand at room temperature for 5 minutes. Sprinkle the remaining jalapeños over the tortilla, cut into 4 wedges, and serve hot or at room temperature.