Preheat the oven to 400 degrees F. Make the croutons: Melt 1 tablespoon butter, then mix with the paprika in a bowl. Add the bread cubes and toss. Spread on a baking sheet and bake until golden, 8 to 10 minutes.
Meanwhile, cook the bacon in a large saucepan over medium heat until crisp, about 8 minutes. Transfer with a slotted spoon to a paper towel-lined plate. Discard all but about 1 tablespoon fat from the pan. Add the remaining 1 tablespoon butter, then add the leeks and garlic; cover and cook until soft, about 5 minutes. Add the broth, 2 cups water, the potatoes and 1/4 teaspoon each salt and pepper; cover and bring to a boil over high heat. Reduce the heat to medium and simmer, partially covered, until the potatoes are tender, about 10 minutes.
Puree half the soup in a blender (remove the filler cap to let steam escape), then return to the pot. Add the cream and bring to a simmer. Add the peas and cook until tender, about 3 minutes. Season with salt and pepper. Serve topped with the croutons, bacon and parsley.
Cook’s Note
When blending hot liquids, first let cool for 5 minutes or so, then transfer to a blender, filling only halfway. Put the lid on, leaving one corner open; Cover the lid with a kitchen towel to catch splatters and pulse until smooth.
When blending hot liquid, first let it cool for five minutes or so, then transfer it to a blender, filling only halfway. Put the lid on, leaving one corner open. Cover the lid with a kitchen towel to catch splatters, and pulse until smooth.