I'm not sure where "TheScienceJerk" is getting his or her information, as the Big Bang is the most scientifically accepted cosmological theory for the beginning of the universe (and the idea that dust particles wouldn't "clump" ignores the force of gravity, which I hope is not in question here
In any event, however, it is quite likely to be difficult to design an experiment about inflation. That said, probably the only approach that might work is to reanalyze some of the data on the smoothness of the cosmic background radiation. The reason inflation arose as a theory was that it's very hard to model a universe that is so anisotropic (i.e. the same in all directions), exactly *because* things tend to clump together, but if the universe expanded dramatically in a sudden way, that would allow for the smoothness that we observe.
Hmmm... while it wouldn't be a *direct* cosmological experiment, there might be some way to create an experiment that could demonstrate that rapid expansion tends to smooth out what would otherwise clump. I have no idea whether this would work, but it's possible that drops of dye on soap bubbles might be made to smooth out by expanding the size of the bubble rapidly, but might stay more clumped if the bubble expands smoothly.
Experiments that start with the phrase "I have no idea whether this would work" are often the most interesting, though