So what is baking soda and baking powder? Well they are not the same thing and they are not interchangeable. They are both leavening agents - a leavening agent is a substance used in doughs and batters that produces carbon dioxide and causes them to rise.
Do not add more baking powder to a recipe because it will:
1. Cause the batter to taste bitter
2. It can cause the mixture to rise too rapidly which will make the air bubbles grow too large and burst in turn causing the mixture to fall.
If you have plain flour and want to make self-raising flour then mix two teaspoons baking powder to a cup of plain flour then sift a few times.
Want to make your own baking powder:
To make 1 tsp of baking powder you need:
- 1/2 tsp cream of tartar
- 1/4 tsp baking soda
- 1/4 tsp cornstarch (Add this ingredient if you plan to store it as cornstarch absorbs moisture in the air preventing a premature chemical reaction between the cream of tartar and baking soda)
A quick note – you have to work quickly when using homemade baking powder.