Grenache is another secondary wine grape growing in popularity. I have been slow to coming to truly like Grenache as a grape, but really enjoying it more recently. I have been tasting more decent wines from Châteauneuf-du-Pape and have been able to discern the more pleasurable characteristics of Grenache. We also recently have a tremendous Australian Grenach (the 2006 Cirillo 1850 Grenache) which was wonderful with Korean BBQ.
The characteristics I love about Grenache (and Tempranillo) is that they make hearty, chewable wines that are still elegant and well-refined. It almost seems to be a contradiction in terms, and that is why some of the cheaper, younger Grenache wines don't work. The compexities and balance are not there yet.
The 2006 Cirillo 1850 Grenache was 100% Grenache. But often the Grenache grape is blended with smaller quantities of other grapes. The 2006 Perrin & Fils Châteauneuf-du-Pape Les Sinards is such a blend being 70% Grenache, 15% Shiraz, and 15% Mourvedre. This blending is typical of a wines from Châteauneuf-du-Pape and why there can be such a wide variety of different tasting wines from that region.
Grenache (or a Grenache blend) works well with Sheperd's Pie because both the texture of the wine and the taste compliment the food beautifully. This wine is 'meaty' on its own and mixes with the juice from the pie in a splendid sensation of flavours. Additionally, the leaner, elegant characteristics compliment the mash potato used in the pie.
I have not tried a Pinot Noir with Sheperd's Pie and you may be asking why as it contains lamb mince. I think most Pinot Noirs would be too light in texture to work with the heartiness of Sheperd's Pie.
If you have not tried Grenache before, you owe it to yourself to do so. And if you are going to cook up Sheperd's Pie, then you definitely should be looking for a bottle of Grenache to go with it (or a bottle of a Tempranillo). For my palate, a Grenache is a far better match for Sheperd's Pie than Cabernet Sauvignon or Shiraz.