| 1 | In a blender combine watercress, basil, garlic, olive oil, and parmesan; blend to form a paste. |
| 2 | Add cream and blend only until mixed; do not overblend. |
| 3 | Transfer mixture to a bowl and stir in walnuts and green onion. |
| 4 | Season with salt and pepper. |
| 5 | Mixture will thicken as it stands. |
| 6 | If desired, add a tablespoon of milk or water to thin it out before serving. |
| 7 | Mixture will keep up to 10 days, refrigerated. |
| 8 | Makes 2 cups |