Heat the olive oil in a large skillet on high heat, add the lamb and cook, stirring to brown it. After 3 minutes, add in the vegetables, garlic, oregano and chili flake. Continue to cook until lamb is completely cooked through, then add tomato paste. Cook for another minute and deglaze with red wine. Add in the parsley, soaked raisins, clams, and stock. Cover the pot with a lid and cook until all of the clams are opened. Toss in the cooked pasta (which should still be hot from just being cooked.) Add in the butter, then salt and pepper to taste. The sauce should thicken, but if it needs thickening, add some of your pasta water. The starch released from the pasta will help thicken your sauce. Garnish with olive oil, Greek yogurt and chopped mint. Serve the pasta either family style or individually.