• Adjust rack to top position and preheat oven to 450 degrees. Wash and dry produce.  • Trim and discard root ends and dark green tops from leeks; halve lengthwise. Rinse thoroughly, removing any grit between layers; pat dry with paper towels. Lay flat and thinly slice leeks crosswise into strips. Dice potatoes into ¼-inch pieces. Halve ciabatta. Quarter lemon.

• Heat 1 TBSP butter (2 TBSP for 4 servings) and a drizzle of olive oil in a medium pot (large pot for 4) over medium heat. Add leeks; cook, stirring occasionally, until softened and slightly browned, 4-5 minutes. • Turn off heat; transfer leeks to a small bowl. Wipe out pot.

• In pot used for leeks, combine beans and their liquid, potatoes, cream sauce base, half the mozzarella, half the Parmesan, half the garlic powder, 1½ cups water, 2 tsp pepper, and 1¼ tsp salt (3 cups water, 4 tsp pepper, and 2½ tsp salt for 4 servings). Cover and cook, stirring occasionally, until potatoes are tender and mixture has thickened, 7-10 minutes. • Transfer leeks back to pot; stir to combine.

• While soup cooks, in a second small microwave-safe bowl, combine remaining garlic powder and 2 TBSP butter (4 TBSP for 4 servings). Microwave until butter has melted, 30 seconds. Stir to combine.

• Place ciabatta, cut sides up, on a baking sheet; drizzle with garlic butter. Top with remaining mozzarella and remaining Parmesan. Bake on top rack until browned and cheese melts, 5-7 minutes. • Halve cheesy garlic bread on a diagonal.

• Divide soup between bowls and top with a squeeze of lemon juice. Serve with cheesy garlic bread and any remaining lemon wedges on the side.