Preheat oven at 350F/180C.
Place butter in a small sauce pan and heat on medium until melted. Then, continue to heat until there are no more bubbles coming up and the whistling has reduced (about 5min). Pass your brown butter through the sift. Set aside.
In a mixing bowl, whisk together confectioner sugar, flour, hazelnut and almond flour.
Using a spatula carefully fold in the egg whites and vanilla paste.
Finally, add the melted butter, and whisk gently until smooth.
Place your Medium Tartlet Flexipan® Tray on the top of your perforated baking sheet.
Then, pour your batter into the Flexipan® with the mini ladle.
Add a teaspoon of apple butter in each wells.
Bake for 20 minutes at 350F/180C. (Every oven heats differently, monitor your financiers from 15min)
Once your financiers are out of the oven, let them cool down for about 10min. Then, Unmold, Serve and Enjoy! Bon Appétit!