PawnSac: <mjk: 17... Qb6 18.e5 has the threat of 19.Qxh7 Ke7 20.e6+. So maybe 19... g6 20.dxc6 Qxc6 21.exd6+ with 3P, development, Black's K in the center all for the piece.>
I think you mean 17... Qb6 18.e5 with the threat 19.Qxh7 <Kf7> 20.e6+. So maybe <18>... g6 <19>.dxc6 Qxc6 <20>.exd6+
The line being 17... Qb6 18.e5 g6 19.dxc6 Qxc6 20.exd6+
But after 17... Qb6 18.e5 g6 19.Bxd6+! and now if
a) ..Kd7 20.dxc6! (threatening Bxf8 discovered check and white has his peice back with a powerful passed pawn) 20. ..Kxc6? 21.Qc4+ forking the rook.
b) ..Kf7 20.f5! gxf5 (..Bxf5 21.g4!) 21.e6+ Nxe6 22.Qxf5+ Ke8 23.Qf7+ Kd8 24.Qxg8 and blacks position totally collapses
c) ..Ke8 20.Na3 and white has dangerous threats. If black plays 20. ..Bxd6 then Nc4, if 20. ..cxd then 21.Nb5! Bxd6? 22.exd6! with multiple threats of Nc7+, Rae1+, or Qxd5. White has 3 pawns for the piece with attacking potential.