Duck with beef heart and buckwheat in the oven

First we wash the duck in running water, then we put the duck carcass in water with salt and vinegar and let it brew for one hour. After we take out the duck and let it dry.
Preparing the filling for duck with buckwheat
Fry onions in vegetable oil in a frying pan. Add to it the giblets cut into small pieces (heart, stomach, liver, you can meat), mix. We continue to fry until the giblets are slightly browned. We also put buckwheat washed in cold water here. Stir and add the broth (you can just use hot water). At the same time, we take into account the following proportion: each glass of buckwheat is equal to one glass of liquid.
Sprinkle with pepper and crushed garlic. Fry over low heat, stirring, until half of the liquid from the pan is absorbed into the buckwheat. We immediately remove it.
Cooking duck
Now we coat the duck inside and out with a mixture of garlic, salt, pepper, adjika and mayonnaise. Let it stand for about an hour and a half.
After filling the duck with buckwheat, we tie its legs so that they do not diverge, and close the hole with the "tail" so that the filling does not fall out.
Now you can just put the duck on a baking sheet greased with oil. And you can put it on foil. And put it in the oven at 190 degrees. Bake until cooked, watering with juice, which will begin to stand out from the duck.