Step 1

Preheat oven to 300 degrees. Toast bread for 15-20 minutes, flipping once during the cooking. Let cool slightly and process in food processor or blender to create breadcrumbs. Toss crumbs with the melted butter, and a good pinch of salt and pepper. Spread in a single layer on your baking sheet and toast for an additional 10-15 minutes, until golden brown.

Step 2

Bring a large pot of salted water to a boil. Cook the pasta to al dente.

Step 3

Brown the garlic in a large skillet over medium heat. Add the crushed fennel seeds and red pepper flakes along with the bread crumbs and let heat together until the flavors meld.

Step 4

Drain the pasta, reserving the cooking water. Toss the pasta in the skillet with the bread crumb mixture. Drizzle with olive oil and add additional pasta water if moisture is needed. Sprinkle with parmesan and lemon zest, if desired.