I have pretty adventurous eaters. My daughter got a free dessert from a restaurant when she ordered - and ate - snails when she was six. The whole kitchen was peeking around the door watching this little girl devour slugs (she’d had them before).
But even my kids don’t like everything. My son - as a teenager - just went through a no mushrooms phase that lasted a year. My daughter - the sushi and snail eating girl - doesn’t like spicy or onions. When we go out for Thai, my daughter does chicken satay - because it isn’t spicy. But we go out for Thai (and Indian - I can’t remember what she gets when we eat Indian). My son LOVES spicy.
Mine became fairly adventurous because we are fairly adventurous. We modeled trying new things. We told them it was ok not to like something, but they should try it. No one is a big fan of brussels sprouts in our house, but we’ve tried them. (I have never cooked liver for my kids - I have too many bad memories of liver growing up). We also gave them permission to say no - and if they did it politely, a peanut butter sandwich to get them through - but no more dishes and by the time they were in kindergarten, they had to make their own.
We’ve also, and was when they were older than your grandson, spoke a lot about picky eaters, manners, and why its important to be open. My husband spent weeks at a time in China for work and to gain the respect of the team, put all sorts of frightening things in his mouth (when I first knew him, he was a picky eater. We never ate FISH because unless it came in a can (tuna), he didn’t like it). We told stories like that, which give them kids a reason to overcome reluctance and see trying new things as brave and advantageous.
The other thing that’s been an advantage - once again for when he is a little older - is that my daughter has had so much fun introducing her friends to sushi, oysters, and creme brulee (I’m shocked, but we’ve introduced three teenage girls to creme brulee in the past year). She gets to be the food expert. Mangos were another one (when she was much younger) that her friends had never had.
And the buttered noodle, hot dog, mac n cheese stage still happened around two. I made sure they had a toddler lunch of whatever they were eating (rice and peas was big in my house for a while), made sure that they had fruit and vegetables (sweet potatoes, green beans, apples, grapes were all popular) then dinner was whatever we were eating. They got the opportunity to eat well once a day - and as its been said - that’s about what you get with a toddler.
