Combine the oats with the baking powder, salt and cinnamon
Mix together the egg, vanilla and yoghurt and add this into the oat mixture until combined.
Let the mix sit for 10 minutes, this lets allows the baking powder to activate
Preheat oven to 375
Once the batter has been sitting for 10 minutes, line a baking tray (9x13 inches) with parchment paper, spray with spray oil and carefully spread the batter onto the tray with a silicone spatula (be careful not to over mix as you do this or the batter will sink)
Spray over the top with cooking oil spray
Place in the oven and bake for 25 minutes or until lightly golden and batter cooked through.
I recommend letting it sit for a few minutes before slicing.