One possible reason could be that he's had a bad experience with the taste. Maybe the ramen was made wrong one day and it left a really bad impression on him.
One possible plot could be that Naruto discovers a new secret ingredient for his favorite ramen. This ingredient could be a rare herb only found in a hidden part of the forest. He then tries to convince Teuchi, the ramen shop owner, to use it in the ramen. Along the way, he has to face off against some ninjas who also want the herb for their own purposes.
Perhaps a ninja who has a grudge against Naruto because he once ate all the ramen at a festival, leaving none for the ninja. So this ninja decides to target Ichiraku Ramen and tries to put a curse on the ramen that would make anyone who eats it sick. Naruto has to figure out how to break the curse and stop the ninja.
It could be a fanfiction that focuses on a character in Naruto experiencing withdrawal symptoms related to ramen. Maybe Naruto himself is deprived of his beloved ramen for some reason and the story explores how he copes.
In the original story, Naruto loves ramen. It's a big part of his character. So in this fanfiction, it's a complete opposite. It changes the fundamental aspect of his relationship with food.
Naruto could use his shadow clone jutsu to multitask in the kitchen. One clone could be chopping vegetables, another boiling the broth, and he himself could be preparing the noodles. His speed and agility from being a ninja would also help him serve customers quickly.
Yes, there are some out there. You can start by looking on fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'naruto ramen ban' in their search bars and you'll likely find a variety of stories. Some might be about Naruto being banned from his favorite ramen place for some wacky reason, like he accidentally caused a food fight or couldn't pay his bill.
One reason could be that it's overused. If there were too many fanfictions focusing on Naruto and ramen, the community might want to encourage different storylines.
In the Hidden Leaf Village, a ramen eating contest was announced. Naruto was the first to sign up. As the contest began, Naruto grabbed a huge bowl of his favorite miso ramen. He slurped it down with great gusto, his cheeks puffed out like a chipmunk. His friends cheered him on. Sasuke watched with a smirk, secretly impressed by Naruto's appetite. In the end, Naruto won by a landslide, his stomach full but his spirit even fuller.
One interesting Naruto ramen fanfiction could be about Naruto opening a ramen chain across the ninja world. He uses his popularity and his love for ramen to bring people together over bowls of delicious ramen.