When you talk about one example of a particular type of an uncountable noun, it is possible to use an article with it.
According to the Oxford Dictionary, cheese is normally uncountable, but if you refer to one example of a particular type of cheese, you can also treat it as countable:
a cow's milk cheese
When you apply good to something, you are talking about a particular type of whatever-it-is, so you can treat it as countable:
A man can make a good cheese with 44% moisture; but I don't care if it is 44% or 34%, if it hasn't got the flavor and quality, you cannot sell it. - Annual Meeting of the Wisconsin Cheese Makers' Association
Note that there are other situations when a normally uncountable noun can be countable: see the link I provided above for more examples.