If the mold is more extensive and appears to go deeper into the cheese, use a knife to cut away about half an inch or more until the mold is removed. One exception to these efforts is when you’re dealing with fresh cheeses, like cottage cheese and fromage blanc; if you see mold growing on these, it’s best to toss the whole container.
There are easy ways to prevent mold from getting a toehold in the first place. Start by purchasing pieces that have been freshly cut from a larger wheel, and buy only what you can consume in a couple of weeks. Not only will you see less mold growth, but your cheese will have more flavor. Always wrap aged cheese in a fresh sheet of wax or parchment paper and store in a cold, draft-free part of your refrigerator (the crisper drawer is a safe bet). Every time you unwrap a cheese, use a new piece of wax paper when rewrapping it for storage. This will prevent potential mold transference.