• If using active dry yeast, dissolve it in a small bowl with 50ml of warm water and the sugar. Let it sit for 5-10 minutes until frothy. If using instant yeast, skip this step and mix it directly with the flour.
• In a large mixing bowl, combine the flour and salt. Make a well in the center and add the activated yeast (or instant yeast) and the olive oil. Gradually pour in the remaining warm water, mixing with your hand or a wooden spoon until a dough forms.
• Transfer the dough to a lightly floured surface and knead for about 10 minutes until smooth and elastic.
• Place the dough in a lightly oiled bowl, cover with a damp cloth, and let it rise in a warm place for 1-2 hours, or until doubled in size.

For the Topping:

• In a large bowl, combine the ground meat, chopped onion, tomato, red and yellow bell peppers, minced garlic, tomato paste, red pepper paste (if using), cumin, paprika, black pepper, and salt. Mix thoroughly until well combined.
• Stir in the chopped parsley and lemon juice. The mixture should be thick and spreadable.
• Preheat your oven to 230°C (450°F) and place an inverted baking sheet in the oven to heat.
• After the dough has risen, divide it into 8 equal portions. Roll each portion into a ball.
• On a lightly floured surface, roll each dough ball into a thin circle, about 20-25 cm (8-10 inches) in diameter.
• Spread a thin layer of the meat mixture evenly over each rolled-out dough circle, pressing it gently into the dough with the back of a spoon.
• Transfer the prepared lahmacun to the preheated baking sheet. Bake for 6-8 minutes, or until the edges are crisp and the topping is fully cooked.
• If needed, bake in batches, depending on the size of your oven.
• Serve the lahmacun hot, garnished with fresh parsley and a squeeze of lemon juice. Optionally, sprinkle with sumac for a tangy flavor.