In a medium bowl combine chicken, Vegeta and oil. Mix well with your hands until the chicken pieces are completely coated. Leave it to rest for about 15 minutes, (or 30-60 minutes if you can).

Heat oven to 485°F (250°C).

Grease the baking pan generously and evenly, then place it in the oven so that it heats up.

In a deep bowl combine the dry ingredients and the egg. Mix with a whisk. Then add yogurt, carbonated water, and regular water. Whisk the batter vigorously until it is completely smooth.

Carefully take the pan out of the oven, and pour the batter into it. Shake lightly from side to side so that it distributes evenly. Top batter with chicken pieces and return the pan to the oven. Bake for 25 minutes.

Lower temperature to 395°F (200°C) and bake for an additional 15-20 minutes. The pie should have a golden color, and be on the softer side. If the color moves closer to brown that's a sign it's getting too crispy. To prevent this, cover it with parchment paper.

Near the end of baking, carefully lift up a part of the pie with a fork to check whether it's done on the bottom side. If the bottom is pale, transfer the pan to the lowest rack.

Carefully take the pan out of the oven. Stab the butter with a fork and then smear it generously over the pie, chicken pieces included. Let it rest for 1 minute.

Now, pour and spread heavy cream over the pie and chicken pieces evenly. Turn the oven off and return the pan so it sits in the warm oven for an additional 5 minutes.

Let the pie rest for 20 minutes before eating. It tastes best warm/hot. Optionally top with sour cream.