Ingredients:

  • 2 large yellow onions, thinly sliced (1 lb / 450g)
  • 1 tbsp extra virgin olive oil (15g)
  • 1 tbsp balsamic vinegar (15ml)
  • 1/2 tsp sea salt (3g)
  • 1/4 tsp cracked black pepper (1g)
  • 1 sheet frozen puff pastry, thawed (approx 17 oz / 480g)
  • 4 oz goat cheese, crumbled or sliced into discs (113g)
  • 1 tsp fresh thyme leaves (2g)
  • 1 egg, beaten for egg wash (50g)

Instructions:

  1. Heat the olive oil in a large non-stick skillet over medium-low heat. Add the sliced onions and salt. Cook, stirring occasionally, for 30–40 minutes until the onions transform to a deep, mahogany-colored jam. Stir in the balsamic vinegar and black pepper during the last 2 minutes of cooking, then remove from heat and let cool.
  2. Preheat your oven to 400°F (200°C). Roll out the puff pastry on parchment paper. Using a knife or pizza cutter, slice the pastry into 6 equal rectangles (roughly 3x4 inches). Lightly score a smaller rectangle inside each piece, leaving a 1/2 inch border to create a well for the toppings.
  3. Brush the borders of the pastry with the beaten egg wash. Spoon 1–2 tbsp of the caramelized onion mixture into the center of each tart. Top with a piece of goat cheese and a sprinkle of fresh thyme. Bake for 12–15 minutes until the pastry is puffed and golden brown.