S.W.
I have a 5 1/2 year old and we too deal with dietary restrictions (Celiac). One of the best methods I've tried with my daughter to introduce new food is to get her involved in process of preparing new dishes. We look through cookbooks to find recipes, select ingredients together at the grocery store, and then cook the recipe together. I would imagine with a 7 1/2 year old you might have even better luck with this process.
Warm regards,
S.
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