Season with salt and pepper, cover, and cook until onions have softened, about 40 minutes.
Remove cover, add Worcestershire sauce, olive brine, and honey and cook additional 20-30 minutes, or until golden and jam-like.
Place flatbreads into pre-heated 450° F oven and cook until slightly toasted. Divide onion mixture between flatbreads and top with chopped olives. Return to oven for 10-15 minutes or until flatbread is crusty.