Lunch is part of our pre-nap routine, so I usually can't get away with skipping it. When we are home, we just have an early lunch at 11ish to allow plenty of time (dd is a slow eater as well). When we are out and about and really running late, I sometimes give her a snack in the car, and when she asks for lunch when we get home, I play dumb and say the snack was lunch. When served her favorites she usually eats faster, so I try to keep those around for days we're behind schedule as well. Either way, if I have rushed lunch, I always make sure to allow time for a big snack after nap.