I have been studying the King's Indian Attack a bit recently, and have started reading through Neil McDonald's Move by Move book on it.
Earlier today I played a game against a 2100 on Lichess (I am around 1700 rapid) and attempted to play the KIA against my opponent's e3 Sicilian. After the first few moves I pushed my e4 pawn to e5 like the McDonald book talks about and then my opponent played 10..f6, leaving no way for me to keep my pawn. I thought that if this were viable I must have messed up the move order and quickly resigned after losing my only central pawn. Checking it with the engine, it looks like a slight inaccuracy from my opponent, going from about a -0.5 evaluation to 0.5 in my favour. But why is this? How am I supposed to "punish" this decision?
[Event "Rated Rapid game"] [FEN ""] [Date "2021.04.13"] [Result "0-1"] [UTCDate "2021.04.13"] [UTCTime "04:29:14"] [WhiteRatingDiff "-2"] [BlackRatingDiff "+1"] [Variant "Standard"] [TimeControl "300+8"] [ECO "B40"] [Opening "Sicilian Defense: French Variation"] [Termination "Normal"] 1. e4 c5 2. Nf3 e6 3. d3 d5 4. Nbd2 Nc6 5. g3 Nf6 6. Bg2 Be7 7. O-O O-O 8. e5 Nd7 9. Re1 Qc7 10. Qe2 f6 11. exf6 Nxf6 0-1
I looked in the database for similar games but at least in the masters' database I'm having difficulty finding the common theme in white's winning plan. From what I have seen, I'm thinking black's e6 pawn becomes a target now that it's sad and alone, and maybe if a c4 pawn break was built up, the c4-f7 diagonal to the king is dangerous? Would anyone with a better understanding of chess be able to tell me if this is correct or if there might be anything else wrong with ..f6?