Step 1

Bring a large pot of water to a boil. Generously salt the boiling water; the water should taste like the ocean. Drop your pasta into the water, stir and cook according to the directions on the package. Reserve 1 cup of the pasta water then drain the pasta.

Step 2

While the pasta cooks, add the vegetable oil to a large Dutch oven over medium-high heat. Once shimmering, add the sausage and cook, breaking it up with a wooden spoon, until crispy, browned and cooked through, 5 to 7 minutes. Remove the sausage with a slotted spoon and set aside in a bowl.

Step 3

Reduce the heat to medium and add the onions and fennel. Season with a three-finger pinch of salt and a healthy crack of pepper. Cook, stirring occasionally, until the fennel starts to soften and the onions become translucent, 10 to 12 minutes. Add the garlic and cook, stirring occasionally with a wooden spoon, until softened, about 2 minutes. Reduce the heat to a simmer.

Step 4

Meanwhile, add the olive oil to a large skillet and heat over medium-high heat until shimmering. Add the sourdough cubes and cook, continuously tossing, until golden brown and toasty, 3 to 4 minutes; set aside on a paper towel-lined plate and season with salt.

Step 5

Add the pasta and reserved sausage to the Dutch oven and toss together. Add 1/2 cup of the reserved pasta water and continue to cook, sprinkling with the Parmesan and continuing to toss to marry the pasta to the sauce, until everything is combined. Add the lemon juice and toss one more time, adding more of the reserved pasta water, as necessary, to achieve your desired consistency.

Step 6

Crumble the toasted bread between your hands to create crumbs. To serve, top the pasta with the breadcrumbs, lemon zest and fennel fronds. Enjoy!