When cooked, escarole's sturdy leaves become melt-in-your-mouth tender. Sweet onion and tangy lemon are the perfect foil for its deliciously mild bitterness.
Heat oil in a large skillet over medium-high heat. Add onion, reduce heat to medium, and cook until softened and lightly browned, about 3 minutes.
Each serving is 1 cup.
Increase heat to medium-high. Add escarole in batches, tossing each batch with tongs until wilted before adding the next, until all escarole is wilted, about 3 minutes. Remove from heat, stir in lemon juice, and season with salt and pepper to taste. Serve hot.