[nealabq]

Could you do this with dry corn starch? Shake it up in the bottle and light it before the dust settles.

[hermitcrab]

I'm not sure that corn starch would stay as a fine powder long enough for that to work.

However, if you have a long cardboard tube:

* place the tube vertically with an ignition source at the bottom (small candle perhaps)

* pour fine powder in the top (may need a step ladder if the tube is tall enough)

* satisfying whoosh

Don't look down the tube as you are doing it and don't do it indoors, obvs!

[pbhjpbhj]

A common science demo in UK used to be exploding a cloud of custard powder - ostensibly powdered sugar and cornstarch.

https://youtu.be/aGBT5pwxThU?si=ay9fm_ZaYImIeNK8 is similar to how it was done.

[huhtenberg]

I wonder if adding a static charge to the dust would help it to stay airborne longer.