The striker, 26, ignored the taunts of West Brom stopper Ben Foster to equalise from the spot in the 88th minute.
Fans' favourite Le Fondre said: "Foster asked me where I put my penalties. I replied 'in the net'.
"The proper Reading turned up. That's how we play and how we need to play and we showed our quality with the chances we create.
"We've just looked at the extra details you need and tried to be a bit more organised as a team.
"It's working for us because we have been a lot more solid and given less chances away."
The 11th hour victory put the Royals within three points of the safety zone after winning two home games on the bounce.