For a veggie-packed frittata, swap the potatoes for broccoli
Start to finish: 45 minutes.
Adjust oven rack to middle position and heat oven to 350 degrees.
Whisk eggs, milk, Parmesan, 1 tablespoon oil, tarragon and ¼ teaspoon salt in a bowl until well-combined.
Heat remaining 1 tablespoon oil in a 12-inch oven-safe nonstick skillet over medium-high heat until shimmering. Add broccoli, shallot, turmeric, ¼ teaspoon salt and ¼ teaspoon pepper and cook, stirring frequently, until broccoli is crisp-tender and spotty brown, 7 to 9 minutes. Stir in water and lemon zest and juice and continue to cook, stirring constantly, until broccoli is just tender and no water remains in skillet, about 1 minute longer.
Add egg mixture and cook, using rubber spatula to stir and scrape bottom of skillet until large curds form and spatula leaves trail through eggs but eggs are still very wet, about 30 seconds. Smooth curds into even layer and cook, without stirring, 30 seconds.
Transfer skillet to oven and bake until frittata is slightly puffy and surface bounces back when lightly pressed, 5 to 8 minutes.
Using rubber spatula, loosen frittata from skillet and transfer to a cutting board. Let sit for 5 minutes before slicing and serving.
Per serving: 221 calories, 7g carbohydrate, 15g protein, 15g fat (4g saturated), 434mg cholesterol, 306mg sodium, 2g fiber.