Spring produce snags the spotlight in this nutritious frittata

In a 10-inch cast iron or ovenproof skillet over medium heat, heat the oil until shimmering. Add the leeks and cook, stirring occasionally, until softened, about 4 minutes. Add the kale and cook, stirring often, until wilted, 1 to 2 minutes. At first, the pan will look completely full, but the kale will wilt fast and reduce. Add the parsley, stir to combine and spread the vegetables evenly around the bottom of the skillet.