• Cut the leeks into ¼-inch slices, using most of the leek until it forks into separate leaves.
• In a large pot, melt the nondairy butter over high heat.
• Add the sliced leeks and lemongrass, and sauté until browned, about 2 minutes.
• Pour in the vegetable broth to deglaze the pot and bring the mixture to a boil.
• Add the diced potatoes, reduce the heat to a simmer, cover, and cook for 30 minutes.
• Using an immersion blender, blend the soup until mostly smooth but leave some chunks for a rustic texture.
• Alternatively, use a countertop blender, blending in batches and letting the soup cool slightly first.
• Season with salt and pepper to taste.
• Serve warm, and enjoy!

Note:

• If using a countertop blender, let the soup cool slightly before blending to avoid hot-liquid splashes.