Preheat oven to 350ºF (177ºC). Grease and flour a standard donut pan.
Mix flour and softened butter together using hands. Press and work into a dough to coat all of the flour in butter (this helps them rise).
Add in yogurt and use a fork to mix and combine well.
Split dough into 6 pieces, each weighing about 73g. Gently roll each piece into a rope about 7” long and place in donut pan. Gently press the ends together once in the pan.
Bake for 20 minutes or until set and just starting to become golden around the edges. Allow to sit in pan for 5 minutes, then remove to a cooling rack.
Once donuts are cooled completely, spray or rub lightly with oil or melted butter. Then roll in cinnamon sugar (I use 2 Tbsp maple sugar and 2 tsp cinnamon). Repeat with the remaining donuts.
Notes
*Self-rising gluten free flour can be hard to find in the United States, but luckily you can easily make your own! Check out my super simple recipe.**I recommend using Chobani brand for the best results. I've tried with one other brand and they didn't turn out quite as light and fluffy.