How to Make It
Preheat a grill pan. In a medium bowl, toss the sweet peppers and sliced onion with 2 tablespoons of the olive oil and season with salt and pepper. In 2 batches, grill over moderate heat, turning occasionally, until lightly charred in spots, 8 to 10 minutes per batch. Return to the bowl. Keep the grill pan on.
In a small skillet, heat the remaining 2 tablespoons of olive oil. Add the garlic and cook over moderate heat, stirring, until softened but not browned, about 2 minutes. Scrape the garlic and oil into the pepper mixture. Add the pickled peppers and their brine and toss well. Stir in the parsley and oregano and season the peperonata with salt and pepper.
Brush the bread with olive oil and grill over moderately high heat, turning once, until lightly charred, about 2 minutes total. Transfer to a platter and top with the scamorza. Pile the peperonata on top and serve.