Heat a small skillet over medium heat and add a drizzle of olive oil.
Cook the egg to your preference, either sunny-side up or scrambled, then season with salt and pepper.
Lightly toast the ciabatta roll if desired.
On the bottom half of the roll, layer fresh spinach, tomato, and avocado slices.
Top with the cooked egg and crumbled feta cheese.
Add olives, roasted red peppers, or fresh herbs if using.
Place the top half of the roll on the sandwich and serve warm. This Mediterranean Breakfast Sandwich is best enjoyed fresh.