In a large pot of salted boiling water, cook the pasta until al dente.
Drain the pasta, reserving ½ cup of the pasta water.
In a large saute pan over medium heat, combine 2 tablespoons of olive oil and 1 tablespoon of minced garlic and cook for 30 seconds.
Add the breadcrumbs and cook for 5 minutes, stirring constantly until golden.
Transfer the breadcrumb mixture to a bowl and toss well with the shredded cheese.
In the same saute pan, heat the remaining olive oil over medium heat. Add the onions, remaining garlic, and chopped fennel. Saute, stirring occasionally for about 10 minutes.
Add the tomato paste and anchovies and stir well. Then, add half the sardines and lightly break them up with your spatula. Then, pour in the raisin and saffron water and season with salt and pepper.
Cook on medium heat, stirring constantly, for another 5 minutes.
Add the cooked pasta, ¼ cup of pasta water, and the vegetable broth. Stir well. If the pasta is too dry at this point, add more of the reserved pasta water.
Continue cooking to heat up the pasta.
Gently stir in the remaining sardines and chopped fennel fronds. Stir well to heat the sardines.
Top with the toasted breadcrumb and cheese mixture and the pine nuts and serve.
Notes
Storage
Refrigerate for up to 4 days in an airtight container.
Freezing is not recommended.
Cook in a saute pan over medium-low heat until warmed, or microwave individual portions at 1-minute intervals.
Tips
Break up your sardines a bit while cooking them, but don't smash them completely.
Stir the garlic continuously as it cooks to prevent burning.
Bring the water to a boil before soaking the raisins to help them plump and release their flavor.