Step 1

Bring a large pot of water to a boil

Step 2

Meanwhile, place the bread in a food processor (or blender) and pulse until uniform coarse breadcrumbs result, about 1 minute

Step 3

Set aside

Step 4

Pour the olive oil from the tin of sardines into a large pan and heat over medium heat

Step 5

Add the garlic and sauté for 1 minute

Step 6

Add the breadcrumbs and stir continuously until golden brown and crunchy, about 4 minutes

Step 7

Remove from the heat to prevent burning, transfer the toasted breadcrumbs to a plate and set aside

Step 8

Clean the pan

Step 9

Heat the EVOO in the same pan over medium-high heat, add the onions and sauté until just caramelized, about 5 minutes

Step 10

Add the sardines, breaking them into pieces with a fork, and mix evenly with the onions

Step 11

Stir in the capers, parsley, lemon zest and red pepper flakes

Step 12

Squeeze in the juice from the lemon

Step 13

Mix the sauce gently and turn off the heat

Step 14

Cook the spaghetti in the boiling water until just al dente, about 7 minutes

Step 15

Drain and reserve ½ cup of the pasta water

Step 16

Add the spaghetti to the sauce, season to taste with salt and pepper and mix until evenly combined

Step 17

Turn the heat to medium, add the pasta water and cook, stirring, until the liquid is absorbed, about 1 minute

Step 18

Sprinkle the pasta with the toasted breadcrumbs, reserving some for serving, then mix again

Step 19

Serve immediately, topping each portion with another pinch of breadcrumbs

Step 20

Garnish with a lemon wedge and sprig of parsley