That boss (oggdo boggdo or whatever) is easily cheesable. You are approaching from within the cave, right? (where you can cut the poles in the way just prior to froggys room). You can go into his room, get a hit or two in (always from the side, abuse the force slow power to help) and then simply retreat back into the cave from where you entered the froggy's room. he can't follow you there, so just regroup and repeat, one safe-ish lick at a time.
You can also fight legit- tricky, but not impossible. You just want to keep to the side of the creature and away from its aggressive forward lunges- don't bother with attempting blocks/parry. He even has a color change tell when he's about to do one of those lunges.
Just don't be greedy, be ready to constantly side dodge and punish him when he commits to a lunge and misses and you got time to get a hit or two in from the side, then retreat and repeat. Again, abuse the force slow as much as you can to ease up your ability to dodge and get to the creatures side and punish it a bit.