In a stand mixer over medium-low speed, mix together the butter, flour and Parmesan cheese, until finely crumbly.
Add optional fresh chopped herbs and black pepper to taste, and knead until you form a dough.
Divide the dough in half. Roll each half into an uniform log, about 3 cm (1¼ inches) in diameter.
Wrap the 2 cylinders into cling film, and refrigerate for 15 minutes.
Preheat the oven to 180°C ( 350°F) without the fan mode. When using the fan-assisted option, set the oven to 20°C less than conventional oven.
Cut each log into 1 cm thick rounds, then you can use a cookie cutter to give them a specific cookie form.
Arrange the cookies on a baking tray lined with parchment paper.
Brush the surface of each cookie with a bit of warm water or a beaten egg, and sprinkle a tiny amount of extra grated Parmesan or chopped fresh herbs on top.
Bake for 10 minutes, or until the cookies are golden on top.
Remove the cookies from the oven, they will still be quite soft. Allow them to cool completely on a baking rack, then serve.
Store leftovers in an airtight container, and refrigerate for up to 4 days.