1. In a sauté pan, thaw the spinach branches for about 15 minutes, adding minced garlic, salt, pepper, and nutmeg to your liking.
2. Preheat your oven to the broil setting.
3. Meanwhile, cook the 4 eggs for 10 minutes until hard-boiled, then peel and cut them in half.
Set aside while you assemble your spinach and egg gratin.
4. Take a baking dish and butter the bottom and sides so that the spinach doesn't stick during the cooking of your spinach and egg gratin.
5. The final step in preparing your gratin is assembling before cooking.
Spread the spinach in the baking dish, then place 2 halves of hard-boiled egg on each small dish.
Next, sprinkle with grated gruyère cheese and put your small dishes in the oven to broil for about 5 minutes.
You can serve your spinach and egg gratin as soon as they come out of the oven.