In a large bowl, mix flour and salt. Gradually add warm water while mixing until a dough forms.

Knead the dough on a clean surface for about 10 minutes until it is very soft and elastic. This is crucial for the layers.

Divide the dough into 2 equal balls. Coat them generously with vegetable oil, cover with plastic wrap, and let them rest for at least 30 minutes.

While the dough rests, heat olive oil in a skillet over medium-low heat. Add sliced onions and cook slowly until deep golden brown and caramelized (about 20 minutes). Set aside.

Preheat your oven to 400°F (200°C) and grease a baking sheet.

On a heavily oiled surface, take one dough ball and press it flat. Gently stretch the edges outwards until the dough is paper-thin and translucent (don't worry if it tears slightly).

Brush the entire surface of the stretched dough generously with the ghee or melted butter.

Scatter half of the caramelized onions and half of the cheddar cheese over the center area of the dough.

Fold the sides of the dough inward over the filling to create a square envelope, brushing with more ghee between every fold.

Repeat the stretching and filling process with the second dough ball.

Place the folded feteers on the baking sheet and bake for 20-25 minutes until they are puffed up and golden brown.

Let cool slightly before cutting into quarters and serving warm.