Grate the carrots on a coarse grater, cut the onion into small cubes.
Heat a frying pan with a little vegetable oil. Add onion and carrot, fry until soft and golden.
Add chicken liver to the overcooked mixture, stir and simmer, stirring occasionally, for 15 minutes.
Salt and pepper the half-cooked liver to taste, pour in water, add mayonnaise, and stir. Simmer, stirring occasionally, for another 15 minutes. Then remove from heat and serve.