Blaziken has equal capabilities in Attack and Special Attack, so there are quite a few options.
Blaze Kick is a great physical Fire attack, and has a high Critical Hit-Ratio. If you want incredibly strong damage though, teach it Flare Blitz instead. The only plus about Blaze Kick is the crit, which hits incredibly hard. However, as you know, Critical Hits are rare. If you want to play it safe though, teach it the ever-so-reliable Flamethrower.
Sky Uppercut is actually pretty good! Never take two offensive moves of the same type though, so dumb double Kick for Brave Bird.
Now we've hit a crossroad: Do you want tactics for your Blaziken, or pure suicidal power? If you want something tactical, teach it something great like Swords Dance. This is only good if you have a Physcial Attack for your Fire-type move. If you don't, then have no fear! You can use Roar to scramble your opponents, or Bulk up to add Bulk AND power to your Blaziken.
If you want Power, teach your Blaziken one of the three attacks:
Poison Jab
(Not great for hitting Super-effective damage, but a chance for poison and a Base 80 power is nice!)
Stone Edge
(Murder those pesky Birds and winged beasts with this hard hitter!)
Shadow Claw
(Punish those psychotic spoon-benders for abusing their magic powers.)
Anyway, catchy lines aside, any of these attacks make Blaziken a great fighter, either built for clean sweeping, manipulating the battlefield, or just for surviving!