But tortillas are considered an unleavened bread, bread in the most general term is just flour and water.

Training routine for next year.

You can also use a large plate the same way.

Not too far fetched. Many vaccines are made with surface proteins from viruses that can be recognized by the immune system. But my guess is going through the pasteurization most proteins would be denatured and not in the functional form.

https://www.chop.edu/centers-programs/vaccine-education-center/making-vaccines/how-are-vaccines-made