In a 4-quart Dutch oven cook onion in hot butter over medium heat about 5 minutes or until onion is tender, stirring occasionally.

Add chicken broth and peas to onion in Dutch oven. Bring to boiling; reduce heat. Simmer, uncovered, about 5 minutes or until peas are tender. Add lettuce; cook 1 minute more or until lettuce is wilted. Remove from heat. Stir in oregano. Cool slightly, about 10 minutes.

Transfer half the hot pea mixture to a blender or food processor. Cover; blend or process smooth. Repeat with remaining pea mixture. Return all to Dutch oven. Break apart goat cheese or cut up cream cheese and add to soup. If using cream cheese, stir in lemon juice. Heat and whisk until cheese is melted and soup is heated through. Season to taste with salt and pepper.

Serve at once in demitasse cups (3-ounce coffee cups) or heatproof small glasses. Makes about 6 cups (eighteen 1/3-cup servings).

Prepare soup through Step 3. Cover and refrigerate up to 2 days. To serve, in a Dutch oven over medium-low heat bring soup to simmering. Remove from heat, serve immediately.