I always find shop bought ones a disappointment having been brought up with them still hot and filled with homemade raspberry jam. As for doughnut stalls selling ring doughnuts, I haven't found one that doesn't smell of old fat. I didn't realise doughnut tins existed, but saw this as a great way to try a healthier version (also a: a good excuse to eat them more often, and b: a good excuse to buy another tin!).
This recipe was enough for 6 big doughnuts and 12 mini doughnuts. You could make half quantity if only one tin. I haven't yet tried keeping 1/2 mix to use again once tin is empty, but it would probably still work (but keep in fridge to slow down growth from the yeast).
Add all dry ingredients to a bowl.
Beat in vanilla, oil and yeast mixture with a balloon whisk.
Transfere mixture to a piping bag (could be spooned in, but would be messier...).
Pipe round the greased rings on the tin.
Leave to rise for 20-30mins.
Bake at 220ºC until lightly browned(10-12mins for large ones and about 8 mins for mini ones). Don't worry about them looking cracked on the tops, they will be smooth and round underneath.
Turn out of the tins and cool on a wire rack.