Preparation

• In large saucepan, melt butter over medium-low heat; cook onions, stirring occasionally, until softened, 10 minutes. Add stock, 1 cup (250 mL) water and potatoes; bring to boil. Reduce heat, cover and simmer for 20 minutes. Add peas; simmer, covered, until peas are tender, 5 minutes.
  
  In batches, transfer to blender or food processor; purée until smooth. Transfer to bowl. Blend in cream; stir in salt and pepper. Refrigerate until chilled, about 4 hours.
  (Make-ahead: Place plastic wrap directly on surface; refrigerate for up to 1 day.)
  Garnish:
  Ladle into bowls; garnish with peas and red pepper.