Prepare the Dough:
Mix warm water, sugar, and yeast in a small bowl. Let sit for 5-7 minutes until frothy.
In a large mixing bowl, combine flour and salt. Add the yeast mixture and olive oil. Mix to form a dough.
Knead the dough on a floured surface for 8-10 minutes until smooth and elastic.
Place the dough in a lightly oiled bowl, cover with a towel, and let it rise for 1 hour or until doubled in size.
Prepare the Filling:
Heat olive oil in a skillet over medium heat. Sauté the garlic until fragrant.
Add chopped spinach and cook until wilted. Remove from heat and let cool.
Combine the cooked spinach, crumbled feta, salt, and black pepper in a bowl. Mix well.
Assemble the Bread:
Preheat the oven to 375°F (190°C).
Punch down the dough and roll it into a large rectangle on a floured surface.
Spread the spinach and feta mixture evenly over the dough, leaving a 1-inch border.
Roll the dough tightly into a log, sealing the edges to keep the filling inside.
Place the rolled bread on a parchment-lined baking sheet, seam side down.
Add the Topping:
Brush the top with the beaten egg for a golden finish.
Sprinkle sesame or nigella seeds on top if desired.
Bake the Bread:
Bake for 25-30 minutes, or until the bread is golden brown and sounds hollow when tapped.
Let it cool slightly before slicing.
Serve:
Slice into thick pieces and serve warm. Enjoy it as a standalone snack or pair with marinara sauce or a fresh salad.