In a large mixing bowl, combine the lukewarm water, yeast, and sugar. Gently whisk them together. Let the mixture stand for 8-10 minutes. You'll know the yeast is active when the surface becomes foamy and bubbly. This crucial step ensures your flatbread will be light and airy.
Once the yeast is activated, whisk in the plain yogurt, 2 tablespoons of olive oil, salt, dried basil, dried oregano, and garlic powder until the mixture is smooth and well-combined.
Gradually add 3½ cups of the flour and the optional fresh parsley to the wet ingredients. Use a wooden spoon or spatula to mix until a shaggy, rough dough begins to form.
Lightly flour a clean work surface and turn the dough out. Knead for 4-5 minutes. The goal is a smooth, elastic dough that is soft and slightly tacky to the touch. If it feels very sticky, add a little more flour, one tablespoon at a time. Be careful not to add too much, as this can make the flatbread tough.
Divide the dough into 10 equal portions. For uniformity, using a kitchen scale is helpful. Roll each portion into a small, smooth ball. Lightly dust the balls with flour, place them on a tray or cutting board, and cover them with a clean kitchen towel. Let them rest for 15 minutes. This rest allows the gluten to relax, making the dough much easier to roll out.
While the dough rests, preheat a dry cast-iron skillet or non-stick frying pan over medium-low heat. Working with one ball at a time, use a rolling pin to roll it into a circle about 7 inches in diameter. Lightly brush the top surface of the rolled-out dough with olive oil.
Carefully place the dough, oil-side down, into the hot pan. Cook for about 1 to 1½ minutes, or until large bubbles start to form on the surface. While it's cooking, brush the top (exposed) side with a little more olive oil.
Flip the flatbread and cook for another minute on the second side until it's golden brown with some darker spots. It should be slightly puffed.
As each flatbread finishes cooking, stack them on a plate and keep them covered with a kitchen towel. The trapped steam will keep them soft and pliable. Repeat the rolling and cooking process with the remaining dough balls. Serve warm.