Melt the butter in a large saucepan, add the spring onions, celery, pea pods or sugar snap peas and split peas and cook for 3–4 minutes, or until beginning to soften. Add the chicken or vegetable stock, bring to the boil, reduce the heat, cover and simmer for 15–20 minutes, or until the split peas and pea pods or sugar snap peas are very tender.
Meanwhile, grill the bacon until crisp, then drain well on kitchen paper. Chop each rasher roughly and reserve to garnish the soup.
Remove the pan from the heat, allow to cool a little, then pour the soup into a blender or food processor. Add the mint and a pinch of grated nutmeg and season to taste. Blend until smooth. Pass through a sieve into a clean saucepan and stir in the cream. Reheat the soup, without boiling, and, if necessary, adjust the seasoning. Pour the soup into a heated tureen or four individual bowls. Crumble the grilled bacon over the top and serve with warm, crusty bread.