We do so like Green Eggs and Ham! Everyday Food editor Sarah Carey cooks up a batch and shows you how to change your omelet cooking method to accommodate the spinach.
In a small nonstick skillet, heat 1 tablespoon water over medium-high. Add spinach and cook, tossing, until completely wilted, about 1 minute. Transfer to a colander to drain, pressing out as much water as possible. Finely chop spinach; transfer to a medium bowl along with eggs. Whisk to combine and season with salt and pepper.
Return skillet to heat and melt butter, tilting to coat pan; add egg mixture. Cook, stirring with a heatproof rubber spatula, until eggs begin to thicken, 30 seconds. With spatula, pull edges of omelet in toward center, tilting pan so uncooked eggs flow underneath. Cook until just set, 15 to 30 seconds.
Arrange cheese and ham on top of omelet. With spatula, fold omelet in half. Transfer to a plate and serve immediately.