Bring a large pot of salted water to a rolling boil. Add the dried spaghetti and cook until al dente, about 8-10 minutes. Reserve ½ cup of pasta water before draining.

In a large skillet over medium heat, add extra-virgin olive oil. Sauté garlic and red onion until soft and fragrant for about 3 minutes.

Stir in chili flakes, chopped tomatoes, and white wine. Simmer for 10-12 minutes until the sauce thickens. Season with salt, black pepper, parsley, and lemon zest.

In a separate pan, heat olive oil and sauté breadcrumbs until golden. Add sardines, capers, and dill, cooking for 2 more minutes. Drizzle lemon juice before removing from heat.

Combine cooked spaghetti with the tomato sauce, adding reserved pasta water for desired consistency.

Plate with sardine crumble on top and garnish as desired.