Shoot raw first and foremost - that'll give you the option to get as much as you can from the file in post-processing.
If it were me (and this applies to anthing where there's a big contrast in tones) I'd watch my blinkies (the overexposure warning on the histogram) to see at what point they kick in as you increase the exposure time/open the aperture. If it's awash with blinkies then you know it's overcooked. Likewise, if your histogram is bunched right up to the left, then you know the shadows will be denser. I watch to get just a small amount of blinkies, knowing that they'll recover in Lightroom and that the shadows have been given as much chance of holding detail as they can get. The it's dow to good processing to bring out the best of the file....