Set your oven to heat at 400 degrees Fahrenheit.
If preparing individual portions, distribute the tomatoes, bell pepper, onion, garlic, and feta cheese evenly into 4 oven-safe ramekins. Drizzle one tablespoon of olive oil over each one.
For a single baking dish, mix the tomatoes, bell pepper, onion, and garlic together and place the block of feta in the center. Pour olive oil over the whole arrangement.
Combine oregano, salt, thyme, black pepper, and red pepper flakes in a small bowl and stir until blended.
Sprinkle this spice blend evenly over the feta and vegetables, dividing it equally if using multiple dishes.
Arrange the ramekins on a baking tray or place the single baking dish on the oven rack and bake for 25 minutes.
Take the dishes out, stir the contents gently to integrate the feta with the vegetables, then fold in the chopped spinach until well mixed.
Make a small well in each ramekin or four wells in the large dish and carefully crack an egg into each.
Return the dishes to the oven and bake for another 10 minutes until eggs are set.
Finish by sprinkling fresh basil or chives on top if desired.
Serve hot, ideally with crusty bread, toast, or pita for dipping.
