Heat the vegetable oil in a pan over medium heat.
Fry the onions, garlic, and ginger for 4 minutes until softened.
Stir in the spices, cooked lentils, and tomato purée.
Cook for 5 minutes until warmed through and stir in the spinach.
Mix flour, salt, and warm water into a dough.
Knead the dough on a floured surface until smooth.
Divide the dough into small pieces and roll into thin circles.
Press black onion seeds into the surface of the dough circles.
Dry fry the chapattis until they bubble and turn golden brown.
Reheat the stew and serve with the warm chapattis.