In a stand mixer, combine the dry ingredients: flour, granulated sugar, brown sugar, baking powder, salt, and cinnamon on a low setting.

In a separate bowl, whisk together the wet ingredients, including the eggs, sour cream, and vanilla.

Gradually fold the wet mixture into the dry ingredients, adding melted butter until a soft dough forms.

Chill the dough in the refrigerator for 30 minutes to firm it up.

Lightly flour your countertop and roll the dough to about ¾ inch thick.

Use a round cutter to cut out donut shapes, then poke a hole in the center with a smaller cutter or your finger.

Place the formed donuts on a parchment-lined tray and refrigerate for another 15 minutes.

Heat canola oil to 350°F (175°C) in a large, deep skillet.

Carefully drop the chilled donuts into the hot oil, frying each for 1-2 minutes on each side until golden brown.

Use a slotted spoon to transfer them to a cooling rack lined with paper towels.

Melt unsalted butter in a saucepan over medium heat until light golden brown.

Whisk in the powdered sugar, cold brew coffee, heavy cream, and vanilla until smooth.

Dip the tops of the slightly warm donuts into the glaze and allow excess to drip off.

Let the glazed donuts set on a wire rack for about 10 minutes.