Bring a pot of water to a boil over high heat. Add the 5 eggs, reduce heat to medium, and simmer for 10 minutes. Remove from heat, let cool, peel, and cut into slices.
In a bowl, mix the Harz cheese, radish sticks, and capers. Season with the oil, lemon juice, a bit of salt, and some freshly ground black pepper.
Arrange the toast pieces on a serving plate. Cover with egg slices, spread the cheese mixture over top, sprinkle with chives, and serve immediately.