How should white finish the deal? What's the best move(s) for white?

 Rc7

Bxg?

1. Rc7 is crushing

e.g.

1. Rc7 R8f7  2. Rxf7 Rxf7  3. Bxe5+

all the other lines I've looked at are just as bad for Black.

Who else has a Queen sacriface?

1 Rc8 is also good.  Then there's 1 Bxe5+ Rxe5 2 Qd4 followed by 3 f4 (what isn't gonna work here?...White is an absurd amount of material up and Black has a hobbled king).

In the actual game, I played Rc7. Here's the full game:

http://www.chess.com/livechess/game.html?id=1893308

c8 forceful move that black must respond to... Black dosen't have any good options & his game falls apart....unprotected pieces & his weak king spells DOOM