You can add a tsp of garlic powder to the mixture, and sprinkle top with parsley or sesame seeds for a savory flavor, or a tsp of vanilla extract and 3 Tbsp of sugar to the egg yolk mixture, sprinkle tops with cinnamon sugar for a sweet flavor before baking. Do not bake this bread on aluminum foil. It will stick and it will be tricky to remove from the baking sheet.
This bread should be good for up to 3 days.
For storing, I recommend keeping it in a zip-lock bag, with small sheets of parchment paper between bread pieces, so they won't stick together. Place in refrigerator for best keeping.