AITAH
MY (27) finances (Michael 28) younger brother (Damian 17) is staying with us for the week.

My soon to be in-laws went away for a trip to commemorate their wedding anniversary and they didn’t want to leave Damian alone. (He didn’t want to go with them either) So he’s staying with us.
Last night my fiance cooked dinner given that he had a day off. He made extra so that I could take some to work the next day. When I woke up this morning I found the tupperware container to which I transferred the food last night empty. I asked Michael if he knew what happened to the food. He had no idea but woke his brother up and he admitted to eating the food. I was a bit annoyed but Michael managed to calm me down and said. “Look honey I cooked the food so really it was mine to share. Damian is a growing lad, he’s constantly hungry.”
That comment annoyed me again But I said nothing and began to look for something to eat for work. That’s when I noticed a jar of my moms cabbage stew on the counter (I am Polish and so is Michael, that’s a Polish dish). I decided that I will take that to work. It was a small one portion jar. My mom often gives me such nice small portion jars of food. We freeze it and save it for days we don’t want to cook.
Then Michael came back to the kitchen and saw me placing the empty jar in the dishwasher. He asked me what I was doing. So I said I’m taking my moms stew to work. He got annoyed and began ranting that he unfroze that jar for his brother to have for lunch as he doesn’t want him cooking and messing up our kitchen. I simply said. “Well darling my mom gave me that jar. So if the food you cooked yesterday was yours to share, that jar is mine. And I am having it.”
He got even more annoyed, called me petty and AH. But am I really the AH for taking food that was cooked by my mom (God bless you mom) and given to me? Especially in such a situation?