1. Preheat oven to 375 degrees F. Grease a 6 cup muffin tin with butter; set aside.
2. Using a rolling pin, slightly flatten each bread slice. Place each slice into each muffin tin cavity. Using a teaspoon, divide spinach, basil, and Swiss cheese amongst the 6 bread cavities. Then, crack an egg on top of each. Sprinkle with sea salt, pepper, chili powder and sesame seeds.
3. Bake for 20-25 minutes or until eggs are set. Remove from oven and serve warm.