In a skillet, heat 2 tablespoons of olive oil over medium-high heat. Add the rinsed capers and fry them for about 2 minutes until golden and crisp. Remove and drain on a paper towel.

Prepare the bread by placing thick slices of baguette on a baking tray. Broil the bread for approximately 2 minutes on each side until golden brown.

In a mixing bowl, flake the sardines with a fork. Add lemon zest, lemon juice, minced garlic, a splash of olive oil, and optional red-pepper flakes. Season with salt and pepper; mix well.

Spread a generous layer of sardine mash onto each slice of toasted bread. Top with crispy capers and sprinkle with parsley or chives.

Serve immediately for the best flavor and texture.