Rye bread or sourdough is recommended for this recipe, or any firmer sliced bread. Lightly spread softened butter (or margarine) on the bread and set it aside.
To a bowl add the eggs, salt, feta and grated cheese and mix fully until combined.
Spread a few tablespoons of the mixture on top of each slice of bread, making sure to cover all the way to the crust. Place your oven rack on the lowest position and set the oven to BROIL (top broiler on). Keep a close eye on the bread while it's in the oven.
Mine took 10 minutes, but the cooking time will really depend on the oven. They are ready as soon as they turn golden and feel firm on top. Sprinkle on some dry oregano or dry savory and enjoy.