Melt the buttery spread in a heavy 4-quart pot over medium-high heat. Add the celery, garlic, and bay leaf. Sprinkle with alittle sea salt and pepper. Stir to coat. Cover and cook for about 15 minutes, stirring occasionally, until the celery has released some of its liquids. Add the herbes de Provence, the dill, and the water. Stir to combine. Raise the heat to high, cover, and bring to a boil. This should take about 10 minutes.
When the mixture reaches a boil, reduce the heat to medium and cook, covered, at a medium boil for about 20 minutes, stirring occasionally until the celery is soft. Taste for seasonings. Transfer about a cup of the soup to a blender. Put the cover on the blender cup then cover the top with a kitchen towel. Wearing oven mitts to protect your hands, pulse several times until blended smooth. Pour this into a clean pot, and repeat to blend the remaining soup. Taste for seasonings. Serve topped with atablespoon or so of toasted pine nuts, if using.
To toast the pine nuts: Arrange the pine nuts in a small skillet and place over medium-high heat. Cook, moving the pan, rotating it to shake the pine nuts and turn them, for about 2-3 minutes until they are golden brown, but not burned. It’s always tempting to pop a pine nut right into your mouth, but wait a minute or two before tasting because they will be really hot.