Turkish Pide

Name: Turkish Pide
Cuisine: German, European, American, Caribbean, Latin American
Ingredients: 2 1/4 cups all-purpose flour, plus extra for dusting; 1 tsp salt; 1 tsp sugar; 1 tsp active dry yeast; 3/4 cup warm water (about 110°F/45°C); 2 tbsp olive oil; For the Topping (Classic Cheese and Spinach); 1 cup feta cheese, crumbled; 1/2 cup mozzarella cheese, shredded; 1/2 cup fresh spinach, chopped; 1/4 tsp black pepper; 1/4 tsp red pepper flakes (optional); 1 large egg yolk, beaten (for brushing); 1 tsp sesame seeds (optional garnish)