How can I secretly make brownies without my mom knowing?(It's for her birthday)
Just clean up when you are done :)
Try doing it when she is at work and you know you will have a lot of time to bake, (maybe decorate) and cool. Don't forget to clean up!
Don't ask her for help.
make them at a friends house.
Do it while she's at work or have your grandparents ask to spend a few hours with her and when your done get rid of the smell by burning a piece of paper, that'll mask the smell and you could pull it off as a bad incense.