In a large mixing bowl, combine flour, salt, baking powder, and instant yeast. Gradually add lukewarm water while kneading until a smooth, elastic dough forms. Knead the dough for 8–10 minutes until it becomes soft and pliable.

Cover the bowl with a kitchen towel and let the dough rise for about 1 hour, or until it doubles in size.

Once risen, briefly knead the dough to release excess air and shape it to fit a greased baking pan. Cover and let it rest for an additional 30 minutes.

Preheat your oven to 430°F (220°C). Bake the flatbread for 20–25 minutes, or until the crust is golden and crisp.

While the flatbread is baking, thinly slice the onions and season them with salt. Let them sit for at least 10 minutes to release their juices and slightly soften.

In a small pan, heat the sunflower oil and add the diced bacon (if using). Fry the bacon until it’s crispy, allowing its fat to blend with the oil.

After baking, carefully slice off the top crust of the flatbread. Cut the bottom half into square pieces, leaving them in place in the baking pan.

Evenly spread the salted onions over the warm bottom layer of the bread. Carefully pour the hot bacon oil over the onions, allowing it to sizzle and infuse the flatbread with rich flavor.

Place the top crust back on the flatbread, cover it with a kitchen towel, and let it rest for about 10 minutes.

Slice and serve the flatbread warm. Pair it with a side of salted sour cream or enjoy it on its own.