Add cumin seeds and once it begins to sizzle, add channa dal (yellow gram). Leave it for a few seconds till it turns to be a little brown and then add onions and fry till it is golden brown.
Add ginger and garlic paste and stir it for a few seconds.
Add red chillies powder, turmeric powder, coriander powder, garam masala and black pepper powder.
Stir it for a minute.
Add in tomato slices, sprinkle salt to taste and fry it again till it melts.
Add sliced bitter gourd and cook it for 8-9 minutes. Serve hot.