Prepare the fish. Cut the fish into portions. Salt and pepper. Heat the frying pan, pour in the vegetable oil. Fry the fish on both sides for 3-4 minutes over medium heat. Add the onion to the fish, after 3-4 minutes, put the carrots in the frying pan. Fry the vegetables with the fish for 1-2 minutes. Pour in the water, cover with a lid and simmer for 10 minutes.