In a food processor, pulse walnuts and dates to a fine, crumb-like consistency. Line a cupcake tray with cupcake liners and divide walnut mixture evenly between cupcake liners. Press the walnut mixture down into the liners to form a crust. Put the "crust" in the refrigerator for 10 minutes to firm up.

Meanwhile, in a large mixing bowl, add Neufchatel cheese, Greek yoghurt, sugar, matcha powder and lemon zest and, using an electric mixer, beat to a smooth consistency.

Spoon cheesecake mixture over crusts in cupcake liners mixture, dividing evenly. Let sit in freezer for 30 to 60 minutes or refrigerate overnight to set. If frozen, let cheesecake sit out on counter for 20 to 30 minutes to defrost before serving. 

Note: Keep in the fridge until ready to serve. If the cheesecakes stay out at room temperature too long, they will start to lose their firm consistency.