Heat the olive oil and butter in a heavy
based pan. When foaming, add the spring
onions and potato. Gently fry without
colouring for about 5 mins. Stir in the
stock, bring to the boil and simmer for
10 mins or until the potato is tender.
Stir in the peas, bring to the boil again,
then cook for about 3 mins until they
are just done. Remove the pan from the
heat, add the mint leaves and whizz in a
blender or food processor until smooth.
To make the Parmesan biscuits, heat
the grill to high. Line a baking sheet with
baking parchment and divide the grated
Parmesan into 6 long strips. Grill for 1 min
or until the cheese has melted and is
lightly golden. While still warm and a bit
flexible, release the biscuits from the
baking parchment with a palette or
cutlery knife, then cool until firm.
To serve, heat the soup and divide
between 6 bowls. Scatter with mint and
sliced spring onions, if you like, and serve
with the Parmesan biscuits on the side.