Creamy Watercress Soup with Toasted Croutons

Preheat oven to 375°F (190°C). Toss bread cubes with olive oil and garlic powder (if using). Spread on a small baking tray and toast in the oven for 8-10 minutes, or until golden brown and crispy. Set aside.

Melt butter in a large pot over medium heat. Add the chopped onion and cook until softened, about 5 minutes.

Add the diced potato to the pot and cook for another 3 minutes.

Pour in the vegetable broth and bring to a boil. Reduce heat and simmer for 15-20 minutes, or until the potato is tender.

Add the watercress to the pot and cook for 1-2 minutes, until wilted.

Remove the pot from the heat and carefully blend the soup using an immersion blender or transfer to a regular blender (in batches). Blend until smooth.

Return the soup to the pot and stir in the heavy cream (if using). Season with salt and pepper to taste.

Heat gently until warmed through. Do not boil.

Serve hot, garnished with toasted croutons.