1 cup (8 ounces) Greek-style yogurt (like Fage or Oikos)
1 tablespoon extra-virgin olive oil
1 teaspoon harissa sauce 
1 garlic clove, minced
Coarse kosher salt
Coarse kosher salt
1 pound carrots, peeled, cut into 1/2- to 3/4-inch pieces
1 3/4-pound turnip, peeled, cut into 1/2- to 3/4-inch pieces
3 tablespoons butter
1/2 pound spring onions or green onions, coarsely chopped (about 1 3/4 cups)
2 tablespoons chopped fresh Italian parsley
2 tablespoons chopped fresh mint
2 garlic cloves, minced
1 teaspoon paprika
1 teaspoon ground cumin
1/2 teaspoon ground coriander
1/2 cup dry white wine
2 teaspoons all purpose flour
1 15-ounce can garbanzo beans (chickpeas), drained, rinsed
1 5-ounce bag baby spinach
1 to 3 teaspoons fresh lemon juice
- Make the yogurt sauce: Whisk first 4 ingredients in medium bowl. Season to taste with coarse salt and pepper. Cover and chill; can be made 2 days ahead.
- Make the vegetable tagine: Bring 8 cups water to boil in heavy large saucepan. Sprinkle with coarse salt. Add carrots; cook until just tender, about 4 minutes. Using skimmer or large slotted spoon, transfer carrots to large bowl of ice water. Return water to boil. Add turnip; cook until just tender, about 3 minutes. Using skimmer, transfer turnip to bowl with carrots. Reserve cooking liquid.
- Melt butter in heavy large pot over medium heat. Add next 7 ingredients. Sprinkle with coarse salt and pepper. Cook until onions are soft, stirring often, about 8 minutes. Add wine; simmer until reduced by half, about 5 minutes. Stir in flour. Add carrots, turnip, beans, spinach, and 2 cups reserved cooking liquid (save the rest of the vegetable stock for another use). Bring to simmer; cook until vegetables are heated through, adding more cooking liquid for desired consistency. Season stew to taste with coarse salt, pepper, and lemon juice.
- Divide stew among bowls. Spoon dollop of yogurt sauce over and serve.
- Beans, Main Dishes