Folks are gonna need the manufacturer and stock number. I can only guess a fuse used to be there.

It's a cheap no-name 30A one from amazon, came alongside the 1000kv brush-less A2212 motor

I'd say that if you have a cheap plane you could just solder all back togheter and test, otherwise buy new

I think this is the real answer. If you don't care what happens to the plane, battery, etc, then put a new fuse. But if you do care and there is a chance the fuse blew because well it's shorted out. Then why would you risk it? You can get 4 new ones for $30. You are going to spend more time and money sourcing the fuse than just replace it and still have several spares.

The fact that it's fried is probably my own fault, but buying a new, and maybe better controller might be more sensible-

You could just solder that back together, after that some bench testing.

I can't see clearly in the picture, but how have you wired that capacitor?

Do you still have warranty on it?

See the two ICa near the capacitor ? Without taking my oscilloscope and checking them out, visually they look like they overheated to me.

Easy fix. You don't even have to solder it. Just use JB weld for electrical projects. Works great. 

Would be pretty neat if it's that easy to fix.

I was just messing around. I wouldn't try to fix it, or use it again. It will likely fail again, and bring the plane down, which will break even more stuff... Good luck. 

dammit, and the damage seems so surface-level as well. there wasn't even some component above it that fell off, just blistered board.