Vegetable oil, enough for frying (corn, canola or sunflower)
1/2C strawberry or raspberry jam or marmalade
White sugar, to finish
Instructions
In a large bowl place the yeast with the milk and mix with a spoon until well blended. Let sit for 10 minutes.
Add in the sugar with the butter, egg yolks and mix for a few seconds. Add the flour (first 3 cups and then the rest if the dough needs it) with the salt and mix again for 1 minute until a slightly sticky dough is formed.
Place the dough on the clean counter and knead by beating and folding it over itself for 15 minutes until you get a smooth and elastic dough. The whole kneading process can also be done in a standing mixer with the dough hook on.
Once ready, form a ball with the dough and put it in a clean bowl with a little oil so that it does not stick. Cover it with a kitchen towel and let the dough rest for 1 hour or until it doubles in size.
Once the dough has doubled in size, place it on a clean, floured surface and roll it out irregularly until it is about 1/2 inch (1 cm) thick. Using a cookie cutter or glass, cut out circles of approximately 2 1/2 inches (7 cm) and place them on a tray or baking sheet with parchment paper underneath. Repeat this step only once more with the leftover dough to make more doughnuts.
Cover the donuts with a kitchen towel and let them rest for 1 hour. Separately, place white sugar on a flat plate to coat the doughnuts after frying. And fill a pipping bag with a round tip with the jam, to fill the doughnuts after they are done.
Put enough vegetable oil in a medium saucepan and bring it to medium heat to heat up. The oil should reach a temperature of about 170°-180° C approximately. It is important that it is not too hot so that the doughnuts cook well on the inside. Cook them enough time for them to fully cook, but make sure they do not burn either.
Once the oil is hot, fry the donuts, three or two at a time, or depending on the size of the pan, but it is important not to add too many at a time. They should cook for approximately 3 minutes on each side. Place them on a plate with kitchen paper to remove the excess oil and immediately coat them with white sugar.
With a plastic or wooden toothpick, make a small hole in the edge of each donut to serve as a guide for filling. Fill the doughnuts by inserting the pipping tip into the hole and squeezing the jam in. Ready!