My daughter dealt with the same thing for awhile. She stopped taking a few of her favorite foods such as salami (smells funny), olives, hummus, and chicken salad. The same kid always made fun of her food and said it looked gross when eating her chicken salad with pita chips. I just reminded her that it’s ok that not all kids like the same thing and unfortunately some kids are not fortunate enough to maybe have tried some of the food she enjoys or be able to take lunch to school and that’s ok. I remind her that it is ok to let the kid know that it might be gross to them but it’s really good to her and if they continued to make comments to inform the teacher. A few days later I asked her if the same child was still making remarks about her lunch and she said no because she sometimes shares her home lunch with them and she will also eat some of the school lunch so she won’t be hungry during the day. I also informed her that she doesn’t have to share her lunch if she doesn’t want to and it’s ok to say no to certain things she does not want to share and remind her that it might not always be safe to share her lunch. I did message the teacher to inform her my daughter sometimes shares her lunch or food and if any kids had any allergies, she thankfully informed me none of the students did.