Heart of palm soup

2 Tablespoons butter
1/2 onion, chopped
1/2 cup celery and leaves, chopped
4 cups vegetable or chicken stock
2 cans hearts of palm, chopped
1 cup crème fraîche
1 avocado
1 fresh tomato, sliced
slices of lemon

Melt butter, add celery and onion and cook until the onion is translucent. Add the stock and the chopped hearts of palm (reserve some). Bring to a boil, reduce heat, cover, and cook over low heat for 30-40 minutes. Puree the soup in batches. Stir in the cream and the remaining heart of palm. Chill until very cold. Serve garnished with slices of avocado and lemon.

Served with dark bread and fresh tomato slices.