Homemade Pistachio Paste
The problem with finding pistachio paste is that Bronte Pistachio Paste is incredibly expensive and difficult to find, but the other commercial brands use milk or oils as part of the blending process.
Alternatively, you can just try making your own like I did, to create a versatile pistachio paste that I've used for everything from cookies to ice cream!
Step by step photos and instructions available at Kitchen Wench.