I figured this pawn would be indefensible and that I would be able to pluck it off at my leisure later. Little did I know.
14... Qa5xa2
I figured I was now effectively 3 pawns up, counting the indefensible d6-pawn. With a connected outside passer, I would just have to weather a middle game k-side attack and then clean up the endgame.
15. O-O Qa2a5 16. Rf1e1 O-O 17. Bf4c1
So, is white's middle game attack going to get going with f2-f4-f5 soon?
17... b5
Black wastes no time mobilizing his q-side majority. Stockfish now rates black at +2.34.
18. Qd1c2 Bc8b7 19. h4
Ah, here comes the white k-side attack.
19... Rf8b8 20. Bc1f4 Qa5d8
Clearing a path for the the q-side pawns to advance.
21. Kg1h2
Possibly preparing Rh1, Kg1, then advance h4-h5, with a bishop sac on h6 if black plays h7-h6. If this is the k-side attack, it is rather slow.
21... Bb7c8
Clearing a path for the the q-side pawns to advance.