Niche: health (food poisoning).
It may be a good idea to write an article or blog about the recent “pistachio recall.”
All topics related to pistachio/salmonella are hot at this moment. You could write, for instance, about Setton Farms. Better yet: write a detailed article on the symptoms of salmonella.
Isn’t it the niche you write for? You can request nonfiction writing prompts on other subjects. Simply leave a comment and tell me what you need.