If it helps, MrsMn's MIL was a good cook. My MIL was ok, but Christmas dinner was taking a hunk of meat and putting it in vinegar and spices for a few days, and call it sauerbraten.
So we still do that. I try not to complain. Much.
My MIL is a terrible cook, and she knows it. She takes pride in eating bland food. The less flavor the better.
When I cook out, I have to make sure her meat has absolutely no seasoning. No flavor. Nothing. Drives me crazy.
My wife used to be like this, but I wouldn’t allow it to stand. She now understands what good food is. She actually is a very good cook. We work together a lot on meals.