Natural Light : Take your photos by a window and turn off all overhead artificial lights.

White Curtain : Hang a white curtain over the window.  This will soften the light and any harsh shadows.  You'll be surprised to see that your photo is actually lighter than if you didn't use the curtain.  No curtain?  Be creative, use a sheet or tea towel.

No Flash : Turn off your flash!  Food taken with a flash will look greasy and have major shadows.

LEFT : This is what my 'set-up' looked like when I was creating the Spring Header.  Notice the white curtains.
 
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