Bring water to a simmer over low heat in a large pot. Cook <quantity>1</quantity> cabbage head for 4m until the leaves begin to soften. Release the leaves from the core with a knife and drain it. Let it cool in cold water

Use a ring cutter to cut the cabbage leaves into a round shape

Cover <quantity>⅓<unit>cup</unit></quantity> of buckwheat with boiling water and let it soak covered for 30m

Small dice the white part of <quantity>1</quantity> leek

Add <quantity>2<unit>tbsp</unit></quantity> of vegetable oil and <quantity>1<unit>tbsp</unit></quantity> of butter to a skillet over medium heat. Add the diced leak and stir

Add salt and black pepper powder to taste and cook until golden brown. Reserve

Mince <quantity>1</quantity> medium chicken breast

Transfer to a bowl and season with the leek, salt, and pepper mix to to taste

Add <quantity>½</quantity> of a beaten egg

Combine all the ingredients

Add the soaked and drained buckwheat, and stir to combine

Fill the cabbage leaves with about 1 tbsp of the mixture and fold it to form the rolls. Place them on a baking plate

Add <quantity>3<unit>tbsp</unit></quantity> of sour cream and <quantity>¼<unit>cup</unit></quantity> of water to a bowl. Stir to combine

Add black pepper powder to taste and stir

Pour the sauce over the rolls

Bake at <temperature>180<unit>°C</unit></temperature> for 15m until golden brown

Plate a cooked cabbage roll and add sour cream to taste. Garnish with chopped parsley to taste. The cabbage roll with buckwheat is ready

Enjoy!