My freezer trick for citrus peels stopped the fruit flies cold.
I started freezing all my orange and lemon rinds in a ziplock for a month before adding them to my worm bin, and it totally fixed the tiny gnat problem I had in my Chicago kitchen.
Haha @thomas_gonzalez I've learned the hard way that timing is everything. My first attempt at frozen peels ended up looking like a crime scene in my compost bin. Do you just toss them in frozen then?