- Heat the oil in a large saucepan, add the leeks and fry until they begin to soften but not brown.
- Add the peas, water and stock and bring to the boil. Turn down to simmer for 10 minutes.
- Add the mint and lemon rind and blitz until nice and smooth.
- Stir in the mascarpone cheese. Season with salt and pepper and leave with a lid on.
- Brush the beaten egg onto one side the bread. Sprinkle with the seeds and press them into the bread. Heat a little oil in a frying pan and fry on both sides until browned. Cut into strips and serve with the soup.