Add the tote (salt), huka hāura (brown sugar), huka one (caster sugar) and iho hūperei (vanilla) in to the slightly cooled brown butter.
Mix together with a whisk for a minute. Don't worry if the mixture looks a little separated, the eggs will fix that.
Add one hēki (egg) and whisk for 20 seconds. The mixture will start to come together. Add the second hēki (egg) and whisk again for 20 seconds.
Add the puehu parāoa (flour), pēkana paura (baking powder) and pēkana houra (baking soda). Stir to combine.
Add the tiakarete to a papa tapatapahi (chopping board) and chop in to chunks. Reserve the biggest pieces for the centre of the cookie pies. Add the rest to the mixture with the nati pēkani (pecan nuts), if you are using them.
Stir everything together. Put the bowl of mixture in the fridge or leave it on the bench for five minutes to thicken.
As it thickens, grease a 12 capacity muffin tray with butter.
Use ⅔'s of the dough to press in to the muffin tins. Make sure you press it firmly in the bottom of the trays and up the sides.
Divide the reserved tiakarete (chocolate) in to the centre of each cookie pie. Now add a teaspoon of pani tiakarete hānati (chocolate hazelnut spread) on top of the tiakrete (chocolate).
Divide the remaining ⅓ of the mixture in to 12 pieces to create the lids. Spread out each piece and press it firmly on the top and down the sides of the tin.
Bake for 18 minutes until they are golden and perfect.