Preheat oven to 180°C fan-forced. Scatter the pistachio kernels onto a small tray and sesame seeds on a second tray. Place into oven, pistachio tray above the sesame seeds tray, cook 6-8 minutes or until lightly toasted. Set aside to cool.
Put the pistachios in a food processor. Pulse until chopped. Transfer to a bowl. Put the almonds in the food processor. Pulse until finely chopped. Add the peanut butter, Weet-Bix, dates, banana and 1 tablespoon of the pistachio, and 1 tablespoon of the sesame seeds. Process until just combined. Transfer mixture to a bowl.
Combine the remaining pistachio and sesame seeds on a tray. Roll tablespoons of the mixture into balls using slightly damp hands. Roll in the sesame mixture to coat. Place into a container in a single layer. Store in the fridge for up to 7 days.