For the stew, heat the vegetable oil in a pan over a medium heat. Fry the onions, garlic and ginger in the oil for 3-4 minutes, to soften.
Add the spices to the pan and stir well. Add the cooked Puy lentils and tomato purée and cook for 4-5 minutes, or until warmed through, stirring occasionally. Stir in the spinach. Set aside.
For the chapattis, mix together the flour, salt and enough warm water to form a dough. Turn the dough out onto a lightly floured surface and knead until smooth and elastic.
Divide the dough into 3-4 pieces, each the size of a small apple, and roll out into thin circles with a rolling pin. Scatter over the black onion seeds and press them down into the dough.
One by one, dry fry the rolled-out dough circles in a frying pan on both sides until they start to bubble up and turn golden-brown.
To serve, heat up the stew and serve with the two or more chapattis (keep any leftover chapattis for another meal).
