God Wizard.
That is all.
you need to post more specifics- for example, starting level... wizards certainly can be BAMFs, but if you're starting at 1st level one arrow could cut all that fun short in a hurry. there are also different kinds of 'broken'- are you looking to deal outrageous damage, be unhittable/invincible, be able to force others to do your will or call an army to do your bidding, or do you just want to accomplish so much in a single round that you wonder why your turns have been so short in the past? you should post a point buy or starting stats too... some builds (like the aforementioned wizard) are fine in fairly low point buys (since they're mostly just concerned about a single stat), but others (like a summoning reach evangelist) need a handful of decent stats (in that case- Wis for bonus spells and DCs, Cha for sermonic performance and to feed quick channel, dex for bonus AoOs, and str for hit/damage) to be successful.
I would disagree about the wizard. I would suggest sorcerer that focuses on save or suck spells that are unmakeable. The bloodline powers help more with that.
Correct me if I'm wrong, but the sorcerer isn't really going to have higher save DCs than the wizard, and they know less spells and have delayed access to spell levels compared to wizards. The only real positive is spontaneous metamagic application.
The reason the "God Wizard" is considered a god is because with the right amount of preparation he has access to some spell that will win the situation.
I'm going to go ahead and say, if you start at 11th+, you can't go wrong with a Half-Elf Oracle with Eldritch Heritage: Arcane. Using Paragon Surge, you could then grab any Cleric or Wizard spell on the fly, for just the cost of one action and a 3rd level spell. It's about as close to ultimate cosmic power as you can get in Pathfinder (well, I haven't read Mythic--maybe something in there is better, but you get the idea).
if god wizard seems to squishy for you, you could go for the old half-elf synthesist summoner who spams the extra evolution feat for phenominal cosmic power.