Pawn sacrifice in Closed Sicilian

This position could have occurred in one of my recent online games

  White to move

White sacrificed a pawn (on b2), but has a surprisingly (to me) strong initiative.
14. e5!! dxe5 15. Nc6!! Out of nowhere, White generates dangerous threats! Black king is stuck in the center and his queenside pieces are not developed, so White opens up files and diagonals just on time.

now probably  best is 15... Qc7 and something like this could happen: 16. Bb6 Qd7 17. Nxe5 Qxd1 18. Rfxd1 O-O 19. Bc5 Re8 20. Bd6 Rd8 21.Bxb7 Bxb7 22. Rxb7 Ne4 23. Nxf7 Rdc8 24. Rc1 and and White maintains winning chances.

But what if Black wants to be ‘shown’?

15…dxc6?! 16. Bxc6+ Bd7 17. Bxa8 Qxa8 18. Qd6!

Black to move. Rb8 is a decisive threat. White is winning. 18… Ne4 19. Rb8+ Bc8 20. Qc7 +-