That's call gentleman la. That's probably the reason she's with him and did not choose any other man.
Each relationship has different ways they threat each other nice. Does not mean in yours don't have others cannot.
Also he did mentioned she does baking. Nowadays girls alot baking also no idea just play phone. U can't choose a perfect person when ownself ain't perfect.
The issue here is not about what the sweat things he does for his girl. The issue is about her temper. Don't la let it out of topic.

TS, there's no other way to deal temper issues than to address it calmly with her. When she explodes next time try to explain to her calmly. Specifically in front of her parents.

U could have said to her nicely, dear, I tried calling u but your phone can't get through and I have no idea on baking stuff and bought the best I thought about. Continue to address her rudeness. Dear, I also do not appreciate the tone u are in and calling me idiot disrespectfully.
Also when u say that do touch her shoulder.
Say it in a way where her mom can hear it and confirm her mom will be sound her daughter next time. (Provided her mom is a reasonable person)

Remember, in a shouting match, who wins? Nobody right. So one person has to calm the situation down. U will earn more respect in that way. Try not to walk away from a misunderstanding.

Walk away only have u tried calmly in order not to escalate it further. Then only continue explain next time when everyone is more calm.