Red onions - 2, thinly sliced (I used my food processor - makes life so easy)
Garlic - 3 cloves, chopped
Heavy cream - half cup
Balsamic Vinegar - 1 tbsp (optional)
Brown Sugar - 1 tsp
Red Chilli Flakes - half tsp
Extra virgin Olive oil - 2 tbsp
Salt & Pepper - to taste
For the Tart:
Parmesan cheese - half cup, grated
Red bell peppers - sliced thinly into long pieces
Milk - 1 to 2 tbsp (or egg wash if you prefer that)
1) Heat olive oil in a pan on medium and add garlic, sliced onions and red chilli flakes, brown sugar and a pinch of salt. Cook on medium, stirring every once in a while until browned. Add the balsamic vinegar and continue cooking the onions until they are caramelized and almost paste like- about 30 to 40 minutes in all. Yes, it takes patience but it's worth it.
2) Pour the cream on the onion mixture and switch off the stove once warm. Season to taste with salt and black pepper and allow to cool a bit.
3) Preheat oven to 425F. Line a cookie sheet with foil. Spread out the thawed puff pastry sheet a little with a light dusting of flour. Fold all 4 sides of the puff pastry sheet about one inch thickness. Brush the edges with milk (or egg wash if using) to create a border for the tart.
4) Using a fork, lightly pierce the inside of the puff pastry sheet (leaving out the borders) - this will prevent the tart from puffing up when baked.
5) Spread half of the parmesan cheese on the base, top with the caramelized onion mixture, top with the remaining parmesan cheese and line the red peppers.
6) Bake for 30 minutes or until crispy and golden brown. Serve warm.