Preheat your griddle to "Sear". If you do not have an electric griddle heat your griddle until a drop of water dropped on the surface dances and sizzles.
In a small bowl whisk the flour, baking powder and baking soda together until well mixed,
In a large bowl mix the mashed potatoes, yogurt and eggs until well mixed but with some lumps.Add in the green onions.
Incorporate the flour mixture into the potato mixture until well mixed and almost smooth. At this time you need to determine if your batter is too thick. If it does not flow off your spoon i.e. clumps off in a mass, you will need to add more yogurt.
Butter your griddle and spoon your batter onto the griddle. I usually make 2"to 3" pancakes. Let it cook on the first side until bubbles appear on the surface of the pancake, the edges look cooked and the bottom is golden brown.
Turn the pancakes and continue to cook on the second side until the the bottom is also golden brown. Serve hot. They go great with applesauce and eggs for breakfast and applesauce and pork chops for supper.