you don need to actually chew the bread. you can just break it up into smaller pieces. which variable will you change in your investigation?

The type of bread (independent variable)

Explanation:

You can just change the type of bread you are eating and just hold it in your mouth to test your hypothesis of not having to chew the bread. It’s the easier thing to change when making the experiment. Now your bread is your independent variable because you are not changing anything else but the type of bread. Not sure if your question is talking about the technical terms for the variable or what actual variable in the experiment, so I put down both.