Cover sunflower seeds with water and let sit for 2 hours. Drain and place the sunflower seeds in a blender with the rest of the cream ingredients. Puree, adding more water as needed, until the cream is smooth. Set aside.
Preheat oven to 400˚F. Chop 1” from the bottom of the asparagus. Place in a roasting pan along with the sliced shallots, garlic, olive oil, and salt. Toss until everything is combined and well coated with the olive oil. Roast asparagus until tender, 30 to 40 minutes. Set aside a few tips of the asparagus for topping.
Heat the water/broth on the stovetop until warm. When asparagus is tender, combine with the spinach and 2 cups of the hot broth mixture in a blender. Puree until smooth, add more broth/water as needed to thin the soup. Set aside extra broth and pour the soup into the pot.
Heat the soup over low until warm. Stir in the lemon juice and 3 to 4 tablespoons of the sunflower cream. Divide the soup into two bowls and top with an extra drizzle of sunflower cream, the asparagus tips, and a few toasted sunflower seeds.
