With the addition of zucchini, this hash becomes something more adventurous than the de rigueur hash you may get in diners. Try this quick-cooking meal for dinner or breakfast -- either way you'll be satisfied.
Rinse potatoes well under cold running water, then drain and thoroughly pat dry. In a large nonstick skillet, heat oil over medium-high. Add onion and potatoes and season with salt and pepper. Cook, stirring frequently, until potatoes are almost cooked through and golden, about 15 minutes.
Add zucchini, reduce heat to medium, and cook, stirring, until zucchini is soft and potatoes are cooked through, 7 minutes. Season with salt and pepper; divide among four plates. To serve, top with eggs.