Wikipedia says Krapfen(Austrian, in Germany they are called Berliner) are the same as French crullers...it could be in the way they are baked/cooked but looking at them I'd say they are filled donuts that lack chocolate toppings :D. Above are vanilla-filled Krapfen with the standard confectioner's sugar on top, should that have been chocolate then I'd have Boston creme! (my...how I miss Dunkin' Donuts!) Krapfens take the sour rather than sweet side with its filling...strawberry and apricot are the most popular ones but I won't say no to those with chocolates or caramel.
Here's a simple recipe I got from a book...Ich helf dir kochen by Hedwig Stuber...
Ingredients (for about 25 Mini-Krapfen):
500g all-purpose flour
250ml lukewarm milk
3 egg yolks (L)
100g melted butter, lukewarm
a pinch of salt
about 750g clarified butter, lard or coconut oil for frying
jam for the filling (pick your choice)
confectioner's sugar for dusting
1. Sieve flour into a large non-sticky mixing bowl and make a well in the center. Add a tablespoon of sugar and the yeast, crumble the yeast as you put them in.
2. Pour lukewarm milk into the well. Add the other ingredients (sugar, egg yolks, melted butter and a pinch of salt).
3. Knead well, either by hand or with a mixer until dough can be easily removed from the bowl. Add a bit more flour if the mixture feels sticky. Let the bowl rest in a warm place for at least 30 minutes or until the dough has almost doubled, cover with a kitchen towel.
4. Roll out the mixture with a rolling pin about 2cm thick and shape your Krapfen. You can also make minis by using your cookie cutter.
5. Leave the pieces on a floured tray, cover again.
6. Heat the oil of your choice in a large pot (or deep-fryer) to 175°C (~345°F).
7. Drop in the dough one at a time. Close the lid after...the steam helps the Krapfen to float...which gives the Krapfen its distinct middle ring (lol). Flip them in case the other side didn't turn brown. Scoop out the Krapfen in time and let sit on paper towels to remove the oil.
8. When they cool, fill them with your favorite jam using a long piping nozzle. Dust with powdered sugar before serving.
Chocolates on top won't hurt too! ;)