Start to finish: 1 hour, 20 minutes
Hands-on time: 1 hour
Servings: 6 (about 10 1/2 cups)

2 tablespoons vegetable oil, preferably grapeseed
1 1/2 cups thinly sliced onion
2 teaspoons minced garlic
1 1/2 pounds carrots, peeled, half cut into 1-inch chunks and half cut into 1/2-inch dice
1 1/2 pounds turnips, peeled, half cut into 1-inch chunks and half cut into 1/2-inch dice
1 1/2 pounds parsnips, peeled, half cut into 1-inch chunks and half cut into 1/2-inch dice
1 small Yukon gold potato (4 to 6 ounces), peeled and cut into 1-inch chunks
4 cups store-bought vegetable or chicken broth
Kosher salt and freshly ground black pepper
1 1/2 tablespoons fresh lemon juice
Crumbled feta cheese for garnish, optional
1 recipe Everything Pita Crisps (see below)

Heat the oil in a large saucepan over medium heat, add the onion and cook, stirring occasionally, until it is softened, about 5 minutes. Add the garlic, and cook, stirring, 1 minute. Add the carrot chunks, turnip chunks, parsnip chunks, and all of the potato, along with the stock and 2 cups of water. Bring to a boil, reduce the heat, and simmer, covered, until all the vegetables are very tender, about 15 minutes.

Fill a blender one-third full with some of the vegetables and liquid and puree until very smooth, transferring it to a bowl. Repeat the procedure until the soup mixture is completely pureed. Return all the soup back to the saucepan, add the diced vegetables, and salt and pepper to taste. Bring the soup back to a boil, reduce the heat, and simmer, covered, until the vegetables are just tender, 10 to 12 minutes.

Add the lemon juice and adjust seasoning, if necessary. Ladle the soup into 6 bowls, sprinkle with the feta cheese, if using. Top with the crisps or serve them on the side.

Everything Pita Crisps

Start to finish: 20 minutes
Hands-on time: 10 minutes
Makes about 3 cups

2 teaspoons poppy seeds
2 teaspoons sesame seeds
2 teaspoons dried garlic flakes
2 teaspoons dried onion flakes
3/4 teaspoon kosher salt
1/4 cup vegetable oil, preferably grapeseed
4 (6-inch) pitas

Preheat the oven to 375°F.

Combine the poppy and sesame seeds, garlic and onion flakes, and salt in a small bowl and stir well. Separate each pita in half to form two rounds, brush the rough side of each pita round with the oil, cut the pita rounds in half and then into strips, and sprinkle with the seed mixture. Bake on the middle shelf of the oven until crispy, 5 to 8 minutes.