In a large bowl put all the ingredients for batter( eggs, cake flour, honey, white sugar, vegetable oil, milk, vanilla extract and baking powder). Combine well. Put in the fridge for 10 minutes to rest.In a clean and absolutely dry bowl of your electrical mixer ( with whisk attachment),whip the egg white until foamy. Add cream of tartar and continue beating on high speed until you get soft peaks. Add 2 tbsp sugar and continue beating until stiff peaks.Gently fold meringue in the batter just until incorporated.Heat a large non-stick pan. Spray it with a cooking spay.Pour 1 tbsp batter onto pan. Try to make a nice , round and even circle. Fry them till the moment you see small bubbles. Flip over onto another side and cook until nice brown color. Remove Dorayaki and let them cool on a plate or a wire rack.Repeat the same with the remaining batter.Spread a tin layer of Nutella over a pancake before you sandwich it with another.I got 11 Dorayaki sandwiches.