Bring a large pot of generously salted water to a boil. Cook the spaghetti until just shy of al dente.
Meanwhile, crush the taralli into coarse crumbs and set aside.
Heat the olive oil in a large skillet over medium-low heat. Add the garlic and cook until lightly golden. Stir in the anchovies, breaking them up until they melt into the oil. Add the crushed red pepper flakes and cook for 30 seconds.
Reserve 1½ cups of the pasta water, then drain the spaghetti.
Add the spaghetti to the skillet and toss in the garlic and anchovy oil. Remove from the heat and stir in the Saclà Wild Garlic Pesto. Add the reserved pasta water a little at a time, tossing until the sauce is silky and coats every strand.
Fold in the parsley, divide among bowls, and top generously with the crumbled taralli. Finish with a drizzle of extra virgin olive oil.