Clean, devein, and wash the prawns/ shrimp
Finely chop the onion and dice the tomato
Add oil to a kadai/or pan
Once the oil is hot, add the chopped onions and sauté until it turns golden brown
Now add the chili powder and turmeric powder. Mix everything well. Sauté for a minute.
Now add the tomatoes. Mix everything.
Let the tomato-onion mixture thicken up
Now add the prawns/shrimp and salt. Mix everything. Sprinkle water if necessary
Let the prawns cook completely and also let the masala thicken up.
Turn off the heat and serve hot.