Chilled zucchini and pea soup

Ingredients

• For the soup
• 2 tablespoons olive oil
• 1 medium leek, chopped (2 cups)
• 2 medium zucchini, sliced
• 4 cups chicken or vegetable broth
• 1 teaspoon sea salt
• 2 1/2 cups frozen green peas
• 1/2 cup well-packed fresh mint
• For the toasts
• Grilled sourdough
• 1/2 cup ricotta cheese
• 2 tablespoons extra-virgin olive oil
• Salt and pepper