This caramelized onion tart recipe is a savory tart made with juicy caramelized sweet onions, crumbled feta, sweet fig jam, and flaky puff pastry.
In a large skillet cook onion over medium heat with some olive oil until softened and add sugar and vinegar. Simmer until sugar is melted, bubbly, syrupy, and a dark golden brown.
Roll out the puff pastry sheet on a flat work surface and transfer to a baking sheet or tart pan lined with parchment paper.
Score the crust about 1 inch from the edges of the puff pastry rectangle with the tip of a sharp knife and poke the inside several times with the tines of a fork.