Preheat the oven to 350 °F . Lightly spritz your doughnut molds with nonstick spray and arrange them on a large baking sheet (so the silicone pans don't flop around as you move them into and out of the oven!)
You don't need to use a piping bag to fill the doughnut molds, but a piping bag really makes it a lot easier. Prepare your piping bag by putting the bag inside a tall glass (or one of those really tall portable coffee mugs) and folding the edges of the bag over the edge of the mug/glass. This makes it much easier to fill! I always fill pastry/piping bags this way.
In a large bowl, whisk together the flour, the spices, the baking powder, and the salt.
In a second bowl. whisk together the canned pumpkin, sugar, yogurt, oil, vanilla extract
Use a whisk to beat in the egg and the egg whites
Use a spatula to scrape the pumpkin mixture into the bowl with the flour mixture. Use the spatula to stir the pumpkin mixture and the flour mixture together until fully incorporated.
Use a large spoon or ladle to scoop the doughnut batter into your prepared piping bag (you'll need to do this in a few batches. You'll be able to fit about ¼ of the batter in a large pastry bag.)
Pipe the doughnut batter into the doughnut molds. You can also use a spoon to spoon the batter straight into the doughnut molds, but I find it's less messy to use the piping bag method.
Put the whole entire baking sheet containing the filled doughnut molds right into the oven. Bake them for about 15 minutes. When they're done, the tops of the doughnuts should spring back when you lightly press on the doughnuts with your finger. A wooden skewer or knife inserted into the middle of a doughnut should come out clean.
While the doughnuts are baking, melt 2 tablespoons of butter in the microwave (about 30 to 40 seconds on high. Be careful to cover with plastic wrap in case the hot butter decides to explode!) Mix the melted butter together with 2 tablespoons of canola oil (or any neutral-tasting oil.)
Stir together 1 cup of granulated sugar and 1 tablespoon of cinnamon in a small bowl.
When the doughnuts are cool enough to touch and handle, unmold them from the doughnut molds.
While the doughnuts are still very warm, use the pastry brush to lightly brush the oil and butter mixture onto each doughnut. Then, dip the doughnut into the bowl with the sugar and cinnamon to coat.
Set the doughnuts on a plate or cooling rack to cool.