In your mixing bowl, add 2 tablespoons of yeast, 3/4 cups of the flour, and 3/4 cups of the milk.

Mix until it forms a paste.

Cover and allow to rest for about 30 minutes.

Add the remaining yeast and milk. Add in the sugar, salt, vanilla, and egg yolks. Mix until completely combined.

Slowly add in the remaining flour, 1/4 cup at a time until completely combined.

Beat the dough until it pulls away from the mixer.

Slowly add in the butter one tablespoon at a time, adding more butter only when the previous tablespoon of butter fully incorporated into the dough.

Place the dough in a lightly greased bowl and cover. Rest the dough in the refrigerator for about an hour and up to 12 hours.

Lightly flour a surface and roll out the dough on this surface. The dough should be a rectangle with dimensions of about 6 x 10 inches.

Sprinkle the ground cinnamon onto the dough and spread evenly around.

Roll the dough along the longest side of the dough to form a long log.

Cut out thin round of about half an inch. Slightly flatten the round by pressing on the cut sides and place them cut side down onto a floured baking sheet.

Cover and allow to rest for about 10 minutes while you heat the oil.

Add oil to a deep fryer or cast iron skillet (if using a cast iron skillet, make sure the dough is at least 3 inches deep). Heat the oil to 360°F.

Take our two wire racks and line the bottom with paper towels.

Fry the doughnuts 2 – 3 minutes on each side, or until they are golden brown. Place on the wire rack.

Mix the ingredients for the glaze and dip the doughnuts in the glaze, removing any excess. Serve warm.

These doughnuts are best the same day, but can be stored in an airtight container up to three days. I recommend rewarming in the microwaves for a few seconds before enjoying.