Preheat the oven to 400F and line a baking sheet with parchment paper.
Add all ingredients apart from basil, nutritional yeast and broth to the sheet pan, seasoning with salt, pepper and olive oil as desired. Roast for 40 to 45 minutes, until everything is softened.
When it's safe to handle, transfer all of the ingredients including basil, nutritional yeast and broth to a high speed blender. Combine until a smooth. Alternatively, transfer the ingredients to a large pot and puree with an immersion blender. Heat back up and enjoy immediately.
Puff Pastry Top (Optional)
Preheat the oven to 400F. Divide the soup into four 2 cup oven safe bowls, with around 1/2 an inch of space from the top. Using a pizza cutter, cut out a disc in thawed puff pastry (I use the flakey crust brand which is accidentally vegan. Brush the edges of your 4- 2 cup oven safe bowls about 5-6 inches in diameter and stir some of the chives into each.Brush the tops of your bowls with a little bit of vegan melted butter. Add the puff pastry rounds over top, and place the bowls on a baking sheet. Bake for 30 minutes, until the puff pastry is "puffed" and browned on top!