For the home cook on a budget or who just isn't interested in the amount of cooking or cleaning necessary to do it for real there are options. I have often walked past the jars of Don Maria mole paste on the shelves of my local bodega. Quite honestly they scare me. I think it is the layer of oil that separates from the paste due to the amount of time they sit. The instructions are pretty simple. You add 1 part paste to 4 parts stock and allow to simmer in a pot. The real test shall be how the taste compares to the real thing.
The first thing I notice about the Don Maria Paste after I pour off the oil is that they are quite solid paste. It takes a bit of stirring and pressing to get all the chunks to combine with the stock. I was able to, with some adjustments, get the paste to resemble mole sauces. Taste is a whole different story. I could see with further tweaking being able to get the darker mole to a passable flavor, the verde was hopeless. I highly recommend making your own Mole Verde. First it is the simplest to make. Second the flavor of a sauce made with tomatillos you just got from the store as opposed to this travesty is infinitely better.
My next test was using mole paste I purchased from the Puebla Market on 9th street. these paste are kept in a refrigerated case in small deli cups with lids. They were around $6 and had none of that oily layer the mole in jars had. They also had no instructions or claims that they would be great until June 2012. The flavor was so much better in the Oaxacan Mole and the Mole Poblano. I could definitely see using them in a pinch for time. the flavor was pretty close to some restaurant moles I have had. I have also seen people Latin people buying these and have read of some restaurants that buy similar paste from Mexico.
If you must buy paste my advice would be to get them at a Mexican grocery where they are refrigerated and fresher. there are also some places online that sell them as well. If you get them in the Italian Market, you can also grab some fresh tortillas from Tortilleria y San Roman.
The Skinny Fat Kid