I've been working and working on getting these right and... I'm nearly there. DH doesn't get it and thinks I should just go back to buying ready made ones, but now It's become a bit of an obsession.
I use US measurements for some reason (couldn't tell you why....) and experimented a bit before deciding on: 2/3 cup flour, 2/3 cup milk, 2 eggs, pinch of salt, pinch of white pepper.
I whisk the eggs and the milk together until it's pretty well beaten then add to the flour and season. Whisk it really, really well.
In the meantime (I let it sit for a bit after beating) heat a tiny bit of oil (too much oil has been my downfall - makes them soggy on the bottom) in each tin until it's REALLY hot (I leave the oil in the oven for a good 10-15 mins on 220) then divide the batter as quickly as possible between the tins.
Bake 'em for a good 15 mins at least and DO NOT OPEN THE DOOR!
I'm still not there, but I'm getting damn close!
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I'm convinced that it's the technique - not the batter - that makes a good pud.