Preheat oven to 180°C. Line a baking sheet with parchment paper. Arrange the flatbread on the baking sheet.
Heat the olive oil in a medium pan over medium low heat. Add the onion and season with a pinch of salt to taste and red pepper flakes. Cook the onions gently until it is softened about 3-5 minutes and stir in the honey, letting the onions caramelize. Remove from heat.
While the onions cook, stir the ricotta and feta cheese in a small bowl. Spread the ricotta mixture over the flatbread.
Top with the honey caramelized onions. Sprinkle the blueberries on top.
Place the naan pizzas into the oven and bake for about 10 minutes, or until the blueberries are just about ready to burst, the cheese has softened, and the naan is toasted.
Remove from oven, sprinkle with fresh thyme and serve immediately.