So, you want to make some Tubby Custard, eh? No problem! No problem at all! Tubby Custard is a magical stuffs! You see, it's sort of like custard, except it's... wait for it... pink! It's pink custard! And that's only the beginning. Just stick around, because it gets so much better.
The first ingredient in Tubby Custard is formed deep in the pits of the Teletubby Land Acid Lake. Someone has to dive down into the lake to collect the moss and other gunk that gathers on the floor of the lake. Now, only someone evil can do this, so you'd better pay Po some good money if you want to make Tubby Custard (unless you can find Ronald McDonald, but he usually doesn't go into Teletubby Land, and nobody else really does either, so Po or another Teletubby is probably your best bet.)
After that, you have to mix it with some pink Slimes and pickle juice. In order to do this, you must slaughter innocent pickles and suck up slimes, preferably with Noo-Noo or the King K. Rool Cannon. Killing these is the only truly evil eat Tubby Custard. Then you must find a creature of Hell or similar demonicness (Teletubbies, Dora the Explorer, or Bob Saget would all work well here. Typhoon Katrina wouldn't, since she's too good, and would only create a hurricane.), and have your demon curse the custard. At this point it should be ready to go, though some like to add an extra serving of frog legs first.
Tubby Custard has a variety of uses. First and foremost, it is a type of food that the Teletubbies eat. Nobody else can eat it because it is highly toxic to non-Teletubbies. If you're not into the whole asploding thing, you can also use it to power machines, as it can be used as a fuel source without running out. It can also be used as a weapon, as it is sticky, toxic, and it smells like dead fish and ammonia. There are even people who use it as a drug, probably as a harder alternative to Heroin and Cocaine.
A certain certain bag-hatted cowboy wizard does not like to drink this stuff, however he serves it to his children when punishing them.