Step 1

*Note: Before starting, it's important to measure the flour accurately to make sure the donuts do not come out dry and crumbly. If you can, it's best to measure by weight using a food scale.If you prefer to use cups, use a spoon to lightly fluffy the flour in the bag then gently spoon it into your measuring cup until it reaches slightly past the top. Use a flat utensil like a butter knife to level off the top. Never scoop flour directly from the bag with the cup or this can pack in more weight worth of flour and dry out the donuts!

Step 2

In a medium bowl, combine flour, cornstarch, baking powder, baking soda, salt, and ground nutmeg. Whisk to combine and set aside.

Step 3

In a separate large bowl, whisk together your sugar and butter. The mixture will be dry and crumbly but the sugar should be moistened with the butter.

Step 4

Add the egg, egg yolk, and vanilla to the butter mixture and whisk to combine. Finally, whisk in the sour cream.

Step 5

Add your dry ingredients to the wet ingredients. Mix everything together until it just starts to form into a sticky dough. Take care not to overwork the dough as it can make the donuts tough!

Step 6

Turn your donut dough onto a lightly floured work surface. Using your hands or a rolling pin, gently flatten the dough into about 1/4 inch thick. Cut your donuts out using a floured 2 & 1/2 inch donut cutter.

Step 7

Transfer the cut donuts onto a piece of lightly floured parchment paper. Gather any scraps of dough and re-roll and cut again. Repeat this process until all the dough is used up. You should have about 10 to 12 donuts.

Step 8

Fill a large pot with high sides with about 2 inches of neutral flavored oil. Set the pot over a stove burner set to medium heat. Preheat the oil to 375°F.

Step 9

Carefully add in your donuts to the hot oil, taking care not to overcrowd the pan. Fry the donuts in batches until golden brown on each side (about 1 to 2 minutes per side). Transfer to a wire cooling rack or paper towel lined plate to drain. Repeat the frying process with the remaining dough.

Step 10

In a medium sized bowl, combine your powdered sugar and 3 tablespoons of water. Whisk together until you get a smooth glaze. If the glaze is too thick, gradually add more water until you reach your desired consistency.

Step 11

Once the donuts have cooled enough to handle, dip the face of each donut in the glaze. Set on a wire rack to allow the excess glaze to drip off. You can serve these donuts right away or set aside for a few minutes to allow the glaze to set.