Toss the spaghettini and oil in a broiler-safe 12-inch skillet until evenly coated. Toast over medium-high heat while stirring frequently until the pasta turns the color of peanut butter and releases a nutty aroma, about 6 to 10 minutes, then transfer to a bowl.

Wipe out the skillet, add the remaining oil, and heat over medium-high heat until shimmering. Add the onion and salt and cook until the onion is softened, about 5 minutes.

Stir in the tomatoes and cook until the mixture is thick, dry, and slightly darkened in color, about 4 to 6 minutes.

Reduce the heat to medium and stir in the garlic and smoked paprika until fragrant. Incorporate the toasted spaghettini, then stir in the water, chickpeas, wine, reserved tomato juice, remaining salt, and pepper.

Increase the heat to medium-high and bring to a simmer. Cook uncovered, stirring occasionally, until the liquid has slightly thickened and the pasta is just tender, about 8 to 10 minutes.

While the pasta simmers, adjust the oven rack 5 to 6 inches from the broiler element and heat the broiler. Transfer the skillet to the oven and broil until the surface of the pasta is dry with crisped, browned spots, about 5 to 7 minutes.

Let the dish cool for 5 minutes, then sprinkle with parsley and serve warm with a dollop of aïoli.