Pour the yeast into the milk and stir to combine. Let it sit for at least 5 minutes.

In the bowl of a stand mixer, add all dry ingredients and mix to combine.

Add the egg yolks, butter and milk/yeast and mix it on low until everything is mixed together.

Turn the speed up to medium and let the machine knead the dough for about 8 minutes or until the dough is soft and smooth.

Transfer the dough to a large bowl, cover with a towel and let it rise for 20 minutes.

Turn the dough out onto a floured board.

Gently pat it (don’t use a rolling pin!) until about 1/2 inch thick.

Using a medium round cookie or biscuit cutter, cut into rounds and place them in a baking sheet dusted with flour. (You can cut your doughnuts any size you want!)

Cover with a kitchen towel and let it rise again until doubled in size, about 30 minutes.

Heat a pot of oil, over medium heat, until a candy or deep fry thermometer reads 375 degrees. If you don’t have a thermometer, just toss an unlighted match into the oil when you think the oil is hot enough. If the match lights, then you can start frying your doughnuts.

Fry the doughnuts until golden brown and set them onto paper towels to absorb the extra grease.

Cut them in half and fill with the cream.

Dust some confectioner’s sugar and cinnamon (optional) on the doughty and serve.

Start by mixing the corn starch on 1/3 of the milk until dissolved.

Add the milk, the sugar, the egg yolks and the corn starched dissolved on the rest of the milk to a sauce pan and cook, over medium heat, for about 5 to 10 minutes or until thickened.

Turn the heat off and add the vanilla extract and the lime zest, if using.

Let it cool before filling the doughnuts.