Heat oven to 400. Thinly slice leeks (only using the light green/white parts, cut off stalk). Roughly cube potatoes and parsnips (no need to peel either).
Add bacon to parchment or foil-lined sheet pan, spaced out. Cook until crisp, about 15 minutes. Set aside to cool when done.
While bacon cooks, heat butter or oil in a large pot or dutch oven over medium, add in leeks and cook for 5 minutes. Add in garlic, mustard potatoes, parsnips, thyme, salt, garlic powder, and some black pepper. Cook for another few minutes, stirring often.
Pour in stock, bring to a boil and then reduce to a simmer. Cover and cook until potatoes + parsnips can be easily pierced with a knife, about 25-30 min.
Add about 2/3 of the mixture to the blender and process until creamy. You can also use a handheld immersion blender. Or you can leave everything whole if you prefer! I like to have a creamy soup with a little texture.
Pour the creamy mix back into the pot and then add in coconut milk, and nutritional yeast. Stir to combine and cook for a few minutes. Taste to see if it needs salt, pepper, or even a squeeze of lemon juice to freshen up. Add more coconut milk or stock if you’d like it thinner. Serve with crumbled bacon on top + fresh parsley.
