In a large bowl, mix the yeast, sugar and warm milk. (Milk should be 108℉). Whisk and let it proof for about 5 minutes.
Add the eggs, butter, vanilla extract and mix well with a whisk.
Now add the flour, salt, and mix. If using a stand mixer, mix on low speed, then when combined, add the speed and knead for about 10 minutes until the dough becomes stretchy, sticky and tacky. This can also be done manually.
Lightly oil a bowl and transfer the dough inside. Cover using a kitchen towel and let it proof until the dough doubles for 1 hour 30 minutes.
Cut a parchment paper into 16 pieces. About
Once proofed, punch it down to release gas, transfer the dough to the flour-dusted work surface and divide it into 12-16 portions.
Form each portion into a golf ball shape and place it on parchment paper. Use your hand to flatten gently.
Use a piping nozzle and press at the center to create a hole. You can flour the nozzle to avoid sticking. Cover and let it rise for 30 minutes.
After 30 minutes, pour oil into a pot over medium-low heat, about 2-3 inches deep. When the oil is just warm (340℉), add the donuts and cook until the bottom turns golden brown for 2 minutes on each side. Keep monitoring the oil temperature.
When cooked, remove from the oil and place on a plate lined with absorbent or paper towel.
Serve as it is or roll them in granulated sugar and serve.