Complete Debacle

MY round-nine game in the Hastings Masters was a debacle from the opening onwards.
Spanton (1954) - Stuart A White (2096)
French Classical, Steinitz Variation
1.e4 e6 2.d4 d5 3.Nc3 Nf6 4.e5 Nfd7 5.Nf3
More popular is 5.f4. The text was recommended by Tarrasch as it gives more chance for piece-play.
5...c5 6.dxc5
This may look strange but it is the main line. White's idea is to blockade Black's central pawns with pieces on d4 and e5.
6...Nc6 7.Bf4 Bxc5 8.Bd3 f6 9.exf6 Nxf6 10.0-0 0-0

This tabiya occurs more than 850 times in ChessBase's 2019 Mega database

11.Re1?
During the game I thought the position after 10...0-0 had occurred in my games several times before, and that I had replied Re1 on at least two of those occasions.
I was wrong, and it is why Black's next move came as big a shock.
11...Bxf2+?!
According to the analysis engines Stockfish10 and Komodo9, much better is 11...e5! Their main line runs 12.Nxe5 Nxe5 13.Rxe5 (13.Bxe5 Ng4 looks even worse for White) Ng4 14.Be3 Bxe3 15.Rxe3 when Black, among other threats, can simply win the exchange with 15...Nxe3.
12.Kxf2 Ng4+?
Again the engines much prefer 12...e5! with Black having a big attack whatever White does with his dark-square bishop, eg 13.Bxe5? (not best, but instructive) Nxe5 14.Nxe5 Ne4+ 15.Kg1 Qb6+ 16.Kh1 Nf2+ 17.Kg1 Nh3+ 18.Kh1 Qg1+ 19.Rg1 Nf2#
13.Kg3 e5?
Ironically, ...e5 is now a mistake.
Best, according to Stockfish10 (Komodo9 agrees with the analysis after being shown the first move), is 13...Rxf4! 14.Kxf4 h5 with a draw by repetition after 15.Qd2 Qd6+ 16.Kg5 Qe7+ 17.Kf4 etc.
14.Bg5
Not 14.Bxe5?? as White's king is much too exposed after 14...Ngxe5 15.Nxe5 Qg5+ (this was something I did manage to see during the game).
14...Qd6
This seems to be Black's best try, as 14...Rxf3 is met by 15.gxf3, but it should not save him.
15.Bxh7+?
After the game SW suggested 15.Nxd5? but I was right during the game to see that 15...e4+ gave Black lots of compensation.
Correct, as pointed out by the engines, is the obvious, once you have seen it, 15.Be4!
15...Kxh7 16.Qxd5 Qg6
This was the move I had missed.
17.Ne4??
Both Stockfish10's 17.h4 and Komodo9's 17.h3 keep the game going with approximately equal chances.
17...Nf6
The tempo gained on White's queen means Black wins a piece.
18.Qc4
18.Nxf6+ is preferred by the engines, but does not save White.
18...Bf5
My next five moves agree with the engines' first choice, but accuracy in a lost position is too little too late.
19.Nxf6+ gxf6 20.Qh4+ Kg7 21.Rad1 e4 22.Qh6+ Qxh6 23.Bxh6+ Kxh6 0-1 (41 moves)