Preheat oven to 400°F (200°C). Grease 12-cup non-stick muffin pan.
In large bowl whisk together eggs. Mix in corned beef, onion, zucchini and cheese.
Divide shredded potatoes into prepared muffin tins. Top potato with egg mixture. Bake 18 to 20 min., or until puffed and golden. Cool 5 min. in muffin pan before transferring egg cups to a plate. Enjoy warm or cool.
Freeze in a plastic zip-top bag and thaw for quick breakfasts or snacks.