I learned this from an old friend. Take you pipe, and find some tobacco that you dont mind wasting. This can be cheap stuff or great stuff, depending on how much you care about the residual flavor.

1. Pack your pipe

2. Tamp it down HARD

3. Lather, rinse, repeat. By now the pipe should be full of tobacco, and tamped down to where you can barely draw any air in.

4. Light your pipe. Light it well, to where the tobacco actually catches flame instead of smouldering.

5. Drive with you pipe out of the window. Do this on a dry day (ie, hasnt rained recently) and point the bowl of your pipe towards the wind. The tobacco with burn hot, and after it goes out (might be a while, a good 5-10 minute drive at least) there should be a nice cake forming.

WARNING: do no do this more than once per day. too much and you could crack your pipe.

Good to know. I quit smoking tobacco all together recently, but this is still a nice trick to get a fast and easy cake in a pipe.

My old man used to smoke the pipe, when I was little I sometimes used them to smoke weed and my dad sometimes commented that what he was smoking had a weird aftertaste.