Turn on the mixer to low speed to avoid spilling the flour, then increase it to medium speed. Mix for 10 minutes or until the dough comes together and looks nice and smooth.

Next, add the softened butter one spoonful at a time, waiting to add more until the previous one is fully incorporated.

While adding the butter, the dough will get a little shaggy and loose at first. Continue to mix at high speed; the dough will come together again.

Mix until all the butter is absorbed, then move it into a large, greased bowl. Cover with plastic wrap and let the dough rise at room temperature for an hour.

Press the dough with your hands to deflate it, cover it again with plastic, then move into refrigerator, letting it rest overnight.

Next day, place the dough on a lightly floured surface and divide it into 20 pieces of 50g each.

Roll each piece into a tight ball using the palm of your hand, then place it on a floured baking tray.

Loosely cover the doughnut balls with plastic wrap (you don't want to squish them) and let them proof in a warm spot until jiggly and doubled in size.

Fill a large pot with canola oil and heat it to 370°F.

To fry at home like a pro, use a candy thermometer; they are cheap and easy to use. This way, you'll always have the right temperature.

Dump the doughnuts in the hot oil, a couple of them at a time (this prevents the temperature of the oil from dropping too much).

Fry them on each side for 2-3 minutes until golden brown, flipping with a long-handled spider skimmer.

Lift the doughnuts using a large slotted spoon, be sure to drain all the oil. Drop them in a tray with a wire rack arranged on top.

Fill a large bowl with granulated sugar or confectioners' sugar and roll the doughnuts in the sugar while they are still warm to coat, then set aside on a cooling rack for 5-10 minutes.

Fill a pastry bag with the jam, then using a chopstick, poke a hole in the side of the doughnut and fill them. Enjoy, and happy Hanukkah!