In a large mixing bowl, combine the flour, salt, and baking powder.
Add the vegetable oil and mix well.
Gradually add warm water, mixing until a soft dough forms. Knead the dough on a floured surface for about 5-7 minutes until smooth and elastic.
Cover the dough with a damp cloth and let it rest for at least 30 minutes.
In a bowl, mix the mashed yellow split peas (or chickpeas) with ground cumin, ground coriander, turmeric powder, chili powder (if using), and salt. Ensure the filling is well combined and seasoned to taste.
Divide the rested dough into equal-sized balls.
Flatten each dough ball into a small circle using your hands or a rolling pin.
Place a spoonful of the filling in the center of each circle.
Gather the edges of the dough to enclose the filling, pinching the dough together to seal it. Gently flatten the filled dough balls with your hands.
On a floured surface, gently roll out each filled dough ball into a thin, round roti. Be careful not to tear the dough and expose the filling.
Heat a skillet or griddle over medium heat.
Place a rolled-out roti on the hot skillet and cook for about 1-2 minutes on each side, or until golden brown spots appear and the roti is cooked through.
Brush the cooked roti with ghee or butter on both sides.
Repeat with the remaining dough balls.
Enjoy your meal!