01 - Preheat oven to 350°F.
02 - Lightly brush each barley rusk with olive oil using a pastry brush. Arrange on a baking tray and bake for 5 to 8 minutes until golden, crisp, and fragrant.
03 - While the rusks toast, combine the finely diced tomatoes, half of the chopped oregano, and a generous pinch of freshly ground black pepper in a mixing bowl. Toss gently to combine.
04 - Remove the rusks from the oven and allow them to cool slightly on the tray, about 2 minutes.
05 - Spoon the tomato mixture evenly over each rusk. Crumble feta cheese generously on top of each portion.
06 - Arrange red onion slices, Kalamata olives, and capers over the feta. Scatter the remaining oregano on top.
07 - Drizzle with additional olive oil and finish with a final crack of black pepper. Serve immediately while the rusks are still crisp.