How to Make It
Cook bucatini according to package directions, adding 2 tablespoons of the salt to the water. Drain and reserve 1 cup cooking water.
Heat oil in a large saucepan over medium. Add onions, and cook, stirring occasionally, until tender and translucent, about 5 minutes. Stir in garlic, and cook, stirring often, 30 seconds. Add harissa, white wine, and crushed red pepper, and cook, stirring often, 30 seconds.
Stir in canned tomatoes, reserved cooking water, and remaining 2 teaspoons salt, and bring to a boil over high. Reduce heat to medium-low; cover and simmer 10 minutes. Add shrimp, and cook, covered, just until the shrimp are pink, about 4 minutes. Stir in cooked bucatini, parsley, and white wine vinegar, and serve immediately.