Onion cut into half rings. Cover with water, add vinegar and pepper. Leave to marinate for 2-3 hours. Make the dough. Whisk egg with vegetable oil. Then add the milk. The flour and the baking powder. Mix well.

Add the mayonnaise. Mix well, the dough is ready.

Now you need to make a form for baking a cake. Take an ordinary sheet of cardboard, draw on it, our autumn leaf. Recede a little from the painted leaf to get the bumpers. Cut with scissors the leaf. Folded edge, forming the sides, fastened with a stapler. Cardboard shape wrapped in foil. Grease with vegetable oil form. Pour it 2/3 of the dough.

Spread a layer of marinated onions.

On top put onions cut into cubes chicken breast. Sprinkle with a little cheese. Distribute the rest of the dough. And again sprinkle with cheese.

Put in preheated oven and bake for 35-45 minutes on a slow fire until Golden brown.