Ingredients
2 tablespoons butter
3/4 pound chipolini onions (whole; pick the smallest you can find)
2 teaspoons demerara sugar (raw sugar)
1/4 teaspoon salt
1/4 teaspoon black pepper
1/2 teaspoon dried thyme
2 teaspoons balsamic vinegar
1 sheet puff pastry, thawed
20 anchovy fillets, chopped
20 black olives in oil, drained and chopped
2 teaspoons olive oil
2 teaspoons chopped fresh thyme
Directions
Preheat oven to 350F. Melt the butter in a large skillet over medium heat. Add the onions and demerara sugar and sauté, stirring frequently, until the onions become tender and start to turn golden. Sprinkle with salt, pepper, and thyme. Stir the mixture and transfer the skillet to the preheated oven. Cook for 20-30 minutes, stirring occasionally, until the onions are wilted, very soft, and are a medium gold throughout.
Add the vinegar during the last 5 minutes of cooking. Remove from the onions from the oven and set them aside while preparing the pastry for the pissaladiere. until they reach room temperature, and then serve.
Raise the oven temperature to 425F. Press the thawed pastry into a rectangle on a 12-inch by 18-inch baking sheet, building it up a bit around the edges. Spread the pastry with the onions, leaving 1 inch of dough uncovered around the edges of the pastry. Sprinkle the anchovy filets and olives on the pissaladière. Bake it for 15 to 25 minutes, until the pastry has puffed up, turned golden, and crisped.
Remove the pissaladière from the oven and sprinkle the olive oil and fresh thyme across the hot surface of the tart. Cut it into rectangles and serve very warm or at room temperature.
