To Make the Donuts:
Preheat your oven to 350°F (175°C).
In a bowl, whisk together the almond flour, baking powder, oat fiber, pumpkin pie spice, and salt until well combined. Set this dry mixture aside.
In a separate, clean bowl, use a hand mixer to whip the egg whites until they form soft, fluffy peaks.
In another bowl, combine the pumpkin puree, brown sweetener, egg yolks, softened butter, and vanilla extract. Mix thoroughly until smooth.
Gently fold the whipped egg whites into the pumpkin mixture until just combined. Be careful not to deflate the whites too much.
Gradually add the dry ingredient mixture to the wet ingredients and mix by hand until a smooth batter forms.
Transfer the batter into a piping bag (or a sturdy food storage bag with one corner snipped off). Pipe the batter evenly into a silicone donut pan that has been lightly sprayed with nonstick spray.
Bake for about 20 minutes, or until a toothpick inserted into a donut comes out clean.
Let the donuts cool slightly in the pan for 5-10 minutes, then carefully transfer them to a wire rack to cool completely while you prepare the glaze.
To Make the Glaze:
Place the cream cheese in a bowl and microwave it briefly (about 10-15 seconds) to soften it, but ensure it doesn't melt completely.
Add the maple extract, vanilla extract, powdered sweetener, and heavy cream to the softened cream cheese. Mix with a whisk until the glaze is smooth and creamy. If you prefer a thinner consistency, add a little more heavy cream or hot water, one teaspoon at a time.
Dip the top of each cooled donut into the glaze, then place them back on the wire rack to allow the glaze to set. For a richer coating, you can double-dip or spread the glaze over both sides.