How can I make brownie in a cup? because when I was in class I made it with my teacher and when it was done it was rubbery.

A standard size mug is fine. I have made this in a 12oz mug and a 16oz mug.
Don’t over mix your ingredients, which can lead to a tough brownie.
Don’t overcook it. Microwaves vary, so start by cooking it 1 minute, and then an additional 15-30 seconds as necessary.
Do not skip the chocolate chips. They make our brownie fudgy.

I will reply with how to make it

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