You sound like me 'notsmartenough'. I was 18 before I ate Chinese food. I was 23 before I ate a paella and I was very reluctant and didn't do it again for another 5 years.
My mother mistrusted any vegetables that weren't green except for potatoes and carrots.
Anything red was deeply bad - tomatoes, peppers. Don't start talking about sweetcorn. IT IS YELLOW AND THAT IS WRONG. WRONG, I TELL YOU!
We used to feed corn cobs to my rabbit. She'd buy them for him in summer - reduced. When I discovered that you could grill them and eat them slathered in butter and they were lovely she was horrified.
My dad was allowed beetroot but we were kept away from it. He was also allowed cauliflower but she used to cross her arms and gravely say that you should never touch it because it gave you wind.
Some green vegetables didn't pass the test either - obviously asparagus, because it was poncey.
Brussel sprouts and brussel tops were fine. No to spinach and kale and weirdly cabbage, which you'd think would have passed her taste/class test.
My dad and I were allowed to eat mushrooms but only if they were fried to the size and appearance of black nipples.
She loved gardening though and would give me her fantastic chillis, peppers, tomatoes and courgette flowers that you could stuff with soft cheese and chopped anchovies and deep fry in egg white batter.
She really liked those. I'd lie about the anchovies. They'd be wrong. But they were so right.