I’ve always enjoyed the challenge of making food for somebody with allergies or on doctor’s orders to restrict their diet, but this is really hard. Foods that tend to increase stomach acid include:
tomatoes
onions
garlic
butter
lard
oil
significant amount of any other fat
chiles
black pepper
cheese
sausage
bacon
any other fatty meat
vinegar
citrus
mayonnaise
sour cream
chocolate
carbonated beverages
caffeinated beverages
Which basically empties my usual bag of tricks for making things taste good.
Simple grilled / broiled / braised meat with steamed vegetables and brown rice / quinoa / farro.
Granola.
Hippie brown rice bowl a la the old macrobiotic fad diet.
I made a soup with kale, spinach, cannellini, chicken broth, rice, and a lot of good soy sauce to give it some flavor. It was the worst thing I’ve ever made that wasn’t a mistake.