In the bowl of a stand mixer or a large bowl using a hand mixer cream together sugar, banana, and vegan butter until pale yellow in color and smooth.
Add baking powder and sea salt and mix well.
While mixer is running, on low-speed, slowly add the flour, a spoon full at a time.
Spray a mixing bowl with vegetable oil spray, line with plastic wrap, spray the plastic wrap with vegetable oil spray. Add the dough all together on top of the plastic and lightly spray the top of the dough with vegetable oil spray. Cover the dough with the plastic wrap . Chill in the refrigerator for 3 to 4 hours, or overnight. The original recipe even said you could prepare this and leave in the fridge for up to 4 days.
Before cutting out donuts. In a 5-quart Dutch oven or heavy bottomed pot pan with a thermometer attached, preheat oil to 350°F to 360°F.
Lightly flour your surface and rolling pin. Roll out chilled donut dough to 1/2-inch thick. Cut-out donuts with a 3-inch round pastry cutter. Use a 1-inch round pastry cutter to cut out the center of each donut. Brush off excess flour from cut-out donuts. Place all the cut out doughnuts and holes on a lightly oiled baking sheet.
Once the oil is hot drop doughnuts, a few at a time, into the oil. When doughnuts surface to the top of oil, frying for about 1 to 2 minutes, then flip them with a slotted spoon. Fry an additional 2 minutes. Flip again. Fry an additional last 1 to 2 minutes. All sides should be evenly golden brown. Remove from oil with the slotted spoon onto a wire rack placed over a baking sheet.
Fry doughnut holes in oil for about 3 to 4 minutes, or until evenly golden brown, flipping halfway through.
To make the vanilla glaze add sifted confectioners sugar, vanilla extract, and 3 tablespoons nondairy milk or water in a bowl and whisk together until totally smooth. It should be a a fairly runny glaze. Add more nondairy milk or water if necessary to get the right consistency that will slowly run off the doughnuts.
Dip one side of the doughnut halfway into the glaze twisting once left, and once right. And then flip glaze side up and place back to the wire rack for the glaze to fully dry and set.
TIPS: Store CAKE DONUTS on plate for up to 24 hours. Loosely covered with parchment paper. They’re best eaten on the day they’re made.