Preheat the oven to 350 degrees F.
Take a cast iron skillet and put it on the stove. Turn the stove on to medium-low flame.
Add vanilla essence, white sugar, and brown sugar to the skillet and stir them well. Then remove the skillet from the heat. Let it aside for 5 minutes until it is not hot, cool enough to be touched by hand.
Add an egg to melted butter. Add both of these into the skillet containing the sugar mixture.
With the help of a fork, whisk the contents together well.
Then add salt, baking soda, and all-purpose flour to the butter and sugar mixture. Again mix well together so that a smooth batter is obtained.
Cut the chocolate bar into small chunks. Add these chunks and chocolate chips into the batter and stir.
Pour the mixture into a round baking pan lined with baking paper. (You can also bake it in the same cast iron skillet)
Bake it in the preheated oven for 10-15 minutes. Keep check of the color of the contents until it turns golden from the edges, however, soft from the middle portion.
Take out the pan from the oven carefully. Dish out the yummy Pizookie. Let it cool down for a few minutes.
Top the warm Pizookie with whipped cream or your favorite ice cream flavor, chocolate syrup, chocolate chips, or toffee bits. Serve it. Bon appetit!