Recipe for Onion Tarte Tatin with 4 Ingredients

Preheat the oven to 180°C. Peel the onions and cut them in half.

Melt butter in a pan and sauté the onions over high heat for 2 minutes on each side. Add a little water and let simmer for 5 minutes. Then add sugar and balsamic vinegar, and let simmer for another 5 minutes.

Place the onions in a flat pie dish with the face down. Pour the remaining juice over them. Then cover with the pastry, folding the edges inward. Prick the pastry with a fork. Bake for 30 minutes at 180°C.

To finish, take the tart out of the oven. Wait 2 minutes before unmolding: place a plate on top of the mold, flip it over; if a few onions stick to the mold, place them back on the tart.