Divide the egg whites into 72g in the bowl of your stand mixer (fit it with the whisk attachment), 72g in a large mixing bowl. 

Blitz your ground almonds, peanut powder and icing sugar in the food processor until well combined and finely ground. Stop it regularly to scrape down and prevent clumping - normally takes 2mins of blitzing altogether in my Magimix. 

Sift the nuts over the egg whites in the large mixing bowl and mix well. It will be a very stiff and sticky mix, that's just fine. 

Add the caster sugar into a small saucepan, add the measured water and bring the heat to a boil. Meanwhile, turn the stand mixer on and start whisking the egg whites to firm peaks. Use your thermometer to monitor the temp of the sugar syrup and when it reaches 118˚C, turn the stand mixer speed down to low-medium and pour the hot syrup in a thin, slow stream onto the egg whites. When all in (scrape out the pan) turn the speed up to high and continue until the bowl is cool to touch and the meringue super white and glossy like white patent leather. Caution - the metal bowls on stand mixers will be very hot so wait for at least 5 minutes before carefully feeling the outside to check it's temperature. 

Fold a big dollop of the meringue into the nut paste in the large mixing bowl to loosen the mixture up. Then add in the rest and fold it until no streaks remain. Now, you are going to continue mixing with your spatula very firmly until you can draw it up through the mixture leaving a visible line that takes 30 seconds to disappear. If it doesn't mix a little more and try again - this stage is important. 

Scrape into a large piping bag and pipe. I use metal baking trays with silicone macaron mats or silicone liners on for preference. Hold the bag vertically and just off the surface of the lined trays. Hold it still and pipe until you have a circle about 1 inch across then stop and pull the bag up sharply. If you've mixed it enough, the peak which forms should be settled by the time you finish piping them all. Leave at least 2-3 inches space between each macaron so not to overcrowd them and allow for a little spreadage when not using mats with wells in. 

Tap the trays of macarons onto the counter top to knock any excess air out up to 3 times - just don’t be too heavy handed!

Leave for at least 30 minutes before baking somewhere cool until a skin forms on the outside. Preheat the oven to 160˚C WITH THE FAN ON. It just works better than an ordinary oven. And I can't recommend using an in-oven thermometer highly enough, do not rely on the dial on your oven!

Cook one tray full at a time for 15 minutes - open the door and test by pushing the macaron a little (very gently) on the top - it should not move. If it wobbles, cook another 2 minutes and test again. These peanut macarons take longer than all ground almonds ones to cook.

Cool on a rack until completely cold before trying to remove from the liners. 

Simply place the butter, cream and sugar in a medium-large saucepan and heat until melted. Then bring to the boil for 5 minutes. 

Take off the heat then mix in the fluff and peanut butter and stir well until smooth. Add in your chopped peanuts and scrape into a bowl to cool. It will be extremely hot so be careful.

Now you need to wait until the nougat is firm enough to mould into little balls/discs to sandwich between the macaron shells and depending on the heat of your kitchen this could take between 15-45 minutes. Check at 15 minute intervals. If it's become too firm, you'll need to return it to the pan to soften a little but if you're checking it regularly, you should have plenty of time to use it up. 

Spoon or pipe a little dot (about 1/3 tsp) of dulce de leche onto the bottom of each macaron shell, squish a small ball of nougat into a disc (a rounded tsp is good) and sandwich together. Don't press hard or your macs will crack (although you can cover this with choccie later!).

Melt your milk chocolate and using a small piping bag or food bag, drizzle it back and forth over the macs and leave to set before serving. As with all macarons, these are best after at least a day to allow the dulce de leche to soften the shells. Store at a cool room temp in an airtight tin until needed.