The rest is easy. I'll post the recipe, whose origins are not known to me, as my mum got the recipe for a friend of hers and you know how it is with mums. they gather and exchange about everything.
So here it goes. You need:
500g of frehsly cut rhubarb
3 eggs
200g of sugar
1 pack vanilla sugar
100g butter
200g flour
1/2 pack baking powder
Heat the oven to about 180°C (hot air).
Mix it all somehow and done. Too vague? *sigh* okay. You will also need one of those:
Mix the eggs, sugar, vanilla sugar and butter really hard until you get a fluffy bright-yellow mass that tastes delicious (advice: don't taste it; you might want to eat the whole batter).
Stift together the flour and the baking powder and mix it with the batter to create a bigger mass of delicious dough.
Then, there's two tricks to use:
First: before you mess with the rhubarb pieces, put some flour on them, it will keep the pieces from sinking in during the baking.
Second: butter and flour the form before pouring the dough in, it will save you from having to piece the cake together again after trying to get it out of it.
Caution: Don't lick the blade unless you're experienced with dangerous weapons. (Or if you're a politician. Then it's totally ok if you cut your tongue off.)
After baking get the cake out of the form and let it cool down a little.
Bon appetit! :)
P.S. you can also bake this cake with all kinds of berries or cherries (not only because it rhymes.) But if you take cherries, remember that unless berries, they have a pretty solid core. Good news is nobody can sue you if they lose teeth when eating your cherry cake as they have to expect something like that when eating it (like fish with bones or olive pits and so on). But if you value your friends, make sure you get rid of the pits first.