Depends - "more bass" is kind of vague, there's a number of options that come to mind, but none will just be "more bass" - generally you'll either be talking more forward/aggressive, or darker/more recessed depending on what you choose. There's also the open/closed question (there are few "bassy" open headphones though), and comfort/style/etc concerns (if any).
Generically, to give you some options (all of which will satisfy "more bass"):
- Audio-Technica ATH-ESW9A
- Bose AE2 and QC15
- B&W P5
- Denon AH-D1100 and D2000
- Kenwood KH-K1000
- Ultrasone HFI-2400 and PRO2900
There's a lot of difference between the cans on this list, so it really depends on what you want, what pleases you, etc. This list isn't meant to be exhaustive either.