I posted that Chez Maman has a Salade Lyonnaise on the menu. Well, I had a chance to try it last night, and it was so eh that now I'm craving a real one and will have to slog through the suggestions below.
It had all the right ingredients, and the egg was beautifully poached. However, the "lardons" were more like bacon bits -- good bacon, but bacon cut in small dice rather than true lardons, and cooked almost crisp. IMO, the lardons make the salad, the oily tender smoked meat with the egg yolk and the cold greens, against the vinaigrette. It was an entirely different salad with the crisp bacon pieces and I was disappointed.
So take Chez Maman off your list in your quest for the perfect Salade Lyonnaise.