How to get a nice brown caramelized loaf?

Here's a shot of a recent, representative loaf:

http://oldwithoutmoney.com/sourdoughLoafnBuns.jpg

A some significant cracking along one end & side, but reasonable form, decent results from scoring, a decent crust, and it tasted yummy good.
(Baked in a loaf pan at 425.)

But none of that brown caramelizing that characterized many a fine loaf.

What can I do to get that nice brown color? 

Thanks

 - Richard
www.oldWithoutMoney.com