Follow these simple steps to create your own 30-Minute Caramelized Onions Brie Prosciutto Cups:

1. Preheat Oven: Preheat your oven to 400°F (200°C).
2. Caramelize Onions: In a large skillet, heat the olive oil over medium heat. Add the sliced onions and a pinch of salt. Cook, stirring occasionally, for about 10 minutes until the onions are soft and golden brown.
3. Add Balsamic: Stir in the balsamic vinegar and cook for another 2-3 minutes, allowing the flavors to meld. Season with salt and pepper.
4. Prepare Puff Pastry: On a lightly floured surface, roll out the puff pastry. Cut it into squares large enough to fit into a muffin tin.
5. Assemble Cups: Gently press each square of puff pastry into the muffin tin slots. You’ll want to create a small cup shape.
6. Layer Ingredients: Place a small piece of brie cheese at the bottom of each pastry cup. Top with a spoonful of the caramelized onions and a piece of prosciutto.
7. Bake: Place the muffin tin in the preheated oven and bake for 15-20 minutes, or until the pastry is golden and puffed.
8. Garnish: Remove the cups from the oven and let them cool for a few minutes. Garnish with fresh thyme leaves if desired.
9. Serve: Carefully remove the cups from the muffin tin and arrange them on a serving platter.

By following these steps, you’ll create an incredible appetizer that is sure to wow your guests and leave them craving more.