Add water to pot of pressure cooker, set to reduce, and bring to a simmer.
Once simmering, add the tea bags, baking soda, and fruit/herbs, if using.
Close lid and valve. Cook at high pressure for 5 minutes. Allow pressure to release naturally.
Strain the tea into a large container, add sweetener 1 tbsp at a time, tasting in between. Tea will be a bit bitter when hot, so be cautious not to over-sweeten!