Step 1

In a small skillet, combine breadcrumbs and 1 tablespoon (15ml) olive oil, and cook over medium-low heat, stirring occasionally, until toasted and golden brown, 5 to 7 minutes. Transfer breadcrumbs to a small bowl, and season lightly with salt. Set aside.

Step 2

In a Dutch oven or medium pot, bring 3 quarts of water and 1 teaspoon salt to a boil over high heat. Add spaghetti to water and cook, stirring frequently during the first minute to prevent pasta from sticking. Cook pasta until al dente.

Step 3

Meanwhile, in a very large bowl, combine colatura, garlic, and pepper flakes. Whisking constantly, slowly drizzle in 1/4 cup (60ml) olive oil, followed by 2 tablespoons (30ml) pasta water, to form an emulsion.

Step 4

Transfer pasta to bowl along with another 1/2 cup (120ml) pasta water and parsley. Vigorously toss and stir pasta to emulsify sauce and coat with noodles. Add breadcrumbs and toss to combine. Pasta should be well-coated with creamy, emulsified sauce. If it seems dry, add extra pasta water, 1 tablespoon (15ml) at a time, until it reaches the desired consistency.

Step 5

Add lemon zest and taste pasta for seasoning, adding a final splash of colatura if needed. Serve immediately.