1. In a medium saucepan, cook bacon over medium-high, stirring occasionally, until fat is rendered and bacon is crisp, 8 minutes. With a slotted spoon, transfer bacon to a plate. Add onion to pan and cook until softened, 5 minutes. Add tomatoes and paprika and bring to a boil; reduce to a rapid simmer and cook until sauce has thickened slightly, 10 minutes.

2. Meanwhile, in a large pot of boiling salted water, cook pasta according to package instructions. Reserve 1/2 cup pasta water; drain pasta. Return pasta to pot and add tomato sauce; toss to combine, adding enough pasta water to create a thin sauce that coats pasta. Add bacon and parsley, season to taste with salt and pepper, and serve.