When you have macaron shells and filling for the center are ready, then you can assemble macarons.
In the bowl of stand mixer add cold mascarpone cream and whip for a few seconds. Make sure the cream is smooth.
Slowly add ganache that being in the fridge. Whip ganache until smooth and creamy. Do not overwhip ganache!
Place ganache into pipping bag fitted with the round pipping tip.
Pipe Mascarpone Whipped Ganache on one macaron shell leaving space in the center.
Pipe Lady Fingers filling in the center of macaron and top with other shell. You can dust sides of filled macarons with the cocoa powder (optional).
Place assembled macarons into airtight container and keep in the fridge for 12-24 hours before you can enjoy them. Macarons need to mature for better texture and taste.