[yt-users] plotting just contours in a slice

Hi all, I would like to be able to take a slice through a 3D dataset and then plot just the contours of a single variable within that slice. I do not want to overlay the contours with an annotate_countours method. I know one way about this would be to use the FixedResolutionBuffer of some slice plot to reconstruct a mesh-grid and the data, which can then be used within matplotlib directly to create a contour plot. I was curious if there was a more clever method using yt plot objects? Chris