Kale and Fennel Frond Frittata

Set an oven rack about 6 inches from the heat source and preheat the oven's broiler.

Heat olive oil in a small ovenproof skillet over medium heat. Add kale and cook until wilted, 3 to 5 minutes. Add fennel fronds and cook for 1 minute more.

Season beaten eggs with salt and pepper and pour into the skillet. Stir briefly, then leave to allow the bottom of the frittata to set. Once you see the bottom setting, take a spatula to the edges of the pan to ensure that the frittata isn't sticking. When the frittata starts to set around the edges, sprinkle crumbled feta cheese over the top.

Place skillet under the broiler and cook until the frittata is fully set and the edges slightly browned, 5 to 10 minutes. Serve immediately or at room temperature.