Why does Stockfish suggest capturing a bishop in this position when my opponent can fork my king and rook? The position in question is: 

[FEN ""]
[StartPly "13"]

1. d4 c5 2. Nf3 cxd4 3. Nxd4 Nc6 4. Nc3 e5 5. Ndb5 Bb4 6. Bg5 Bxc3+ 7. bxc3 Qa5 8. Qd5 Nge7 9. Nd6+ Kf8 10. Qxf7# 1-0


It's black turn and the engine is recording to take the hanging bishop, but doesn't Nc7+ fork the King and the Rook? Stockfish is still showing a negative evaluation for this position.

Am I missing something important?
White does indeed fork the king &amp; rook after Nc7+ - but after Nxa8, the knight is not escaping, so Black is at worst even on material.

 [FEN ""]

 1. d4 c5 2. Nf3 cxd4 3. Nxd4 Nc6 4. Nc3 e5 5. Ndb5 Bb4 6. Bg5? Qxg5 7. Nc7+ Kd8 8. Nxa8


After something like ...b6 followed by Bb7, the knight's a goner. White can get at most one pawn for the knight (after Nxb6), which leads to a material imbalance of R+P vs B+N. This particular imbalance is roughly equal, although I've also read that the side with two minors tends to be favored in middlegames since they represent two useful attacking pieces while the extra pawn is only useful in the endgame. Moreover, Black is also way ahead in development (even if he does take some time to round up the knight on a8).

In short, you're not missing anything important insofar as White does not end up grievously behind in material - but Black has more than enough positional compensation.