Roasted asparagus and white bean soup

This soup screams Spring. Asparagus. Leeks. New potatoes. When I first saw this recipe in the Food Matters cookbook, I knew I wanted to make it. Simple and subtle, perfect on a chilly Spring night. The white beans and potatoes make it creamy, the white wine departs a dry note, and the asparagus lightens it up, adding the perfect green hue.

I made this recipe twice. The first time I used two large potatoes and it threw off the balance, so I made the soup again with smaller red potatoes. The second time around I blended the roasted asparagus straight into the soup—like Bittman suggests as an alternative (see below)—and I preferred its velvety texture. This soup is subtle, and tastes better the second day with a flavorful garnish like shaved Parmesan, pesto, or smoked paprika.
Since I'm hosting this week's Food Matters Project recipe, the recipe below is Bittman's word-by-word from the cookbook. I've mentioned my changes above. Check out to see what the other members made hereServe the soup with a side of tahini greens, a raw kale salad or this baguette.

Roasted asparagus and white bean soup
Recipe from The Food Matters Cookbook by Mark Bittman
4 tbsp olive oil, plus more for garnish
2 leeks, well-rinsed and thinly sliced
1 tbsp minced garlic
1 tbsp chopped rosemary, or 1 tsp dried
salt and pepper
1/2 c dry white wine
2 baking potatoes, peeled and chopped
3 c cooked or canned white beans, drained, liquid reserved
6 cups vegetable or chicken stock, bean cooking liquid, or water, plus more as needed
about 1.5 lb of asparagus, peeled if thick
One 2-oz piece Parmesan cheese
Makes 4 servings

1. Heat oven to 450. Put 2 tbsp of oil in a large pot or Dutch oven over medium-high heat. When it's hot, add the leeks and cook, stirring occasionally, until softened a bit and beginning to color, 3 to 5 minutes. Add the garlic and rosemary and cook for another minute. Sprinkle with salt and pepper, add the white wine, and stir to loosen the bits of vegetable that have stuck to the bottom of the pan. 

2. Add the potatoes, about half the beans, and the stock. Bring to a boil, the lower the heat so that the mixture bubbles steadily. Cover partially and cook, stirring infrequently, until the potatoes are disintegrating, 20 to 30 minutes; add more liquid as necessary so the mixture remains soupy. 

3. Meanwhile (or ahead of time), put the asparagus in a shallow roasting pan, drizzle with the remaining 2 tbsp oil, and sprinkle with salt. Roast, turning the spears once or twice, just until the thick part of the stalks can be pierced with a knife, 10 to 15 minutes. Remove from oven to cool a bit. Meanwhile, use a vegetable peeler to shave slices from the piece of cheese. 

4. When the soup is ready, mash the potatoes and beans a bit. Chop the asparagus and add it to the pot along with the remaining beans to warm through. Taste and adjust the seasoning. Serve each bowl with some shaved cheese on top.

Pureed Asparagus and White Bean Soup: After you add the chopped roasted asparagus in Step 4, carefully puree the soup in batches in a food processor or blender or with an immersion blender; or simply mash with a potato masher. If you prefer, puree only the beans and broth and add the chopped asparagus before serving.