Unfortunately, you are seriously outclassed for combat against a Fer-De-Lance. It is one of the very best "Fighter" type ships in the game, while a DBE is not even a fighter to begin with. As far as ships which aren't dedicated combat ships go, the DBE is pretty decent at combat, although it isn't the easiest to get the best out of, but it simply isn't a match for an FDL.
Strictly speaking, any ship can beat any other ship, with a sufficient gap in pilot skill, but in reality, beating an FDL requires decent skill and a proper combat ship. At the very minimum, I would say you need a DBS (probably stealthed with lots of HRP's), and that is only if you are very good. A vulture can be a decent match for the FDL, but with the recent buffs to the FDL, probably still needs you to be the better pilot by a noticable margin. I'm not sure about things like Python, FAS, Clipper etc as I haven't flown any of them, but I would think they should all be viable options, and obviously something like a fed Corvette would do the trick.
I would say an FDL is probably good enough to give any ship a run for it's money though, so at the end of the day it will come down to your skill as a pilot.