Most of us immediately reflect on mom's home kitchen when it comes to our first grilled cheese experience. But chances are you ate your first restaurant grilled cheese in one of the many Greek-run diners in this country, especially if you lived along the Eastern Seaboard. This grilled cheese is an homage to that heritage. The olives in the bread heighten the saltiness of the feta; the lamb, a Greek staple, provides a gaminess to balance the saltiness; and the pomegranate and cucumber in the mint salad bring a unique freshness. And once you enjoy the crunch of fried chickpeas, you'll start adding them to nearly everything you make. I know I do.
To make the lamb, in a cast-iron or other heavy skillet, heat the oil over high heat. Add the lamb and cook, stirring to break up the meat with a wooden spoon, until it begins to brown. Add the salt, oregano, and mint and continue to cook, stirring occasionally, for about 4 minutes, until the lamb is cooked through. Remove from the heat.
To make the salad, combine all of the ingredients in a bowl and stir to mix well.
To fry the chickpeas, pour the oil to a depth of 1 to 2 inches into a heavy saucepan or deep sauté pan and heat to 350 degrees F on a deep-frying thermometer. Add the chickpeas and fry for about 5 minutes, until browned and crisp. Drain the chickpeas on a plate lined with paper towels. Transfer to a bowl. Sprinkle with the chili powder and salt and toss to coat evenly.
Line up half of the bread slices on a work surface. Top each slice with 2 ounces (about 1/3 cup) of the cheese, one-fourth each of the lamb, salad, and chickpeas, and then finish with another 1 ounce (about 2 1/2 tablespoons) of the cheese. Close the sandwiches with the remaining bread slices.
Line a large platter with paper towels. In a skillet over high heat, melt 1 tablespoon of the butter. Turn down the heat to low, add 1 sandwich, and cook, turning once, for 2 to 3 minutes on each side, until browned and crisp on both sides and the cheese is melted. Transfer to the prepared platter to blot the excess grease. Repeat with the remaining butter and sandwiches.