Heat 1 tablespoon of olive oil in a skillet over medium-low heat. Add the sliced onions and cook for 25–30 minutes, stirring occasionally, until golden brown. In the last few minutes, stir in the balsamic sauce and a pinch of salt. Remove from heat.
Preheat your oven to 425°F (220°C). Place the flatbread on a baking sheet and brush it lightly with olive oil. Spread the caramelized onions on top.
Add the fig slices and chopped herbs.
Bake for 8–12 minutes, until the flatbread edges are crisp and golden.
Drizzle with honey if you like, then top with arugula and crumbled cheese right before serving.
Serve and enjoy while warm.