Take flour + salt + baking powder and soda in a bowl. And mix.

Take beaten egg + sugar + oil + vanilla essence. And mix and whisk it well.

Now add the dry ingredients to the wet. Then add smashed banana. Also you can add dry fruits at this time.

Add hot water or milk as required. The batter should be little thin.

Now pour it in a baking tin and bake at 160 - 170degree Celsius for about 30 minutes. Check it with a toothpick. If it's clean then its perfectly baked.