Preheat oven to 180C.
In a saucepan heat the rice milk,coconut oil,maple syrup,vanilla extract and vinegar. If using chia instead of an egg,add the chia meal and water to the saucepan. Once combined,set aside.
In a separate bowl,combine dry ingredients and add the warmed wet ingredients and mix well,until it becomes a wet dough (add a little more rice milk if needed). If you are using an egg instead of chia,add it to the dough now.
Spoon the dough into a greased doughnut pan (see note) and bake for 20-25 minutes. Let cool for three to four minutes in the tray. Carefully remove the doughnuts and place on wire rack to cool.
To make the ganache,combine ingredients in a small bowl.
Once the doughnuts are cool,dip them into the ganache and smooth with a knife. Finish by dipping the ganache-covered doughnuts into the crushed hazelnuts.
Tip:These doughnuts are best eaten on the day of baking,otherwise they can be refrigerated for three days or frozen. Bring to room temperature or warm briefly to soften the doughnut before serving.
Note: I've used a doughnut baking tray to bake these doughnuts. You could use a muffin tray if you don't have a doughnut pan and bake these as muffins instead.