The other bakery that albinoni is referring to is Lyndhurst Bake Shop, also on Ridge Road, about 2 blocks closer to Rt. 3 than Mazur's. LBS also has homemade Italian ice that's terrific!
Personally, I like Mazur's for a traditional birthday cake (w/whipped cream, not buttercream for icing), but in general, I think the rest of what they sell is just average.
We do not live near Lyndhurst, and only went to Mazur's once. Their B & W cookies were very boring, and their cupcakes were dry and should have been pulled from the shelf. Reputation seems to be totally undeserved. There is an Italian bakery on the same strip that we once got some good stuff from. Also, I love the stuff at Giancarelli's in Bloomfield.