What's peculiar about pepperoni pizza, Andy? Himself would have that every day and twice on Sunday if I let him. [emoji1]...
His peculiar tastes have to do with hat he will and won't eat. It's hard to feed him any variety because he doesn't like a lot of foods. Pizza was always a hit for him. Especially pepperoni. I sold him on chicken parm by describing it as a giant chicken nugget with cheese on it. So I don't have a lot of flexibility when it's dinner time.
Recently, I got a picky 11-YO, devoted Cheese ONLY pizza eater, to try and LIKE BBQ chicken pizza. His folks were quite surprised. He ate his whole Cheese pizza and 2 slices of BBQ chicken pizza!
But, I always have him try new things when they come to dinner. He gets a "taster plate" before we sit down to eat. You should see the teeniest-tiny little bite he can take to "try" something.