When ready to bake, slice some olives through the middle so you have two halves, then make thin slivers which will be for the eye detail. Break tiny bits off of a sliver to make the froggy nostrils. Push them gently into the rolls where you need to. Brush gently over each with extra milk to glaze, then bake for 12-15 minutes until risen and lightly golden. Leave to cool completely, and then slice to create the froggy mouth and pack full of fillings of your choice. These will keep for a couple of days in an airtight container or food bag.