Jersey Royal Potato & Caramelized Onion Tart

Preheat oven to 200°C (180°C fan/ Gas Mark 6).

In a large pan, melt the Jersey butter over medium heat. Add the sliced onions and cook gently for 25-30 minutes, stirring occasionally, until softened and deeply caramelized. Add the brown sugar and balsamic vinegar in the last 5 minutes of cooking, stirring to combine.

While the onions are caramelizing, boil the Jersey Royal potatoes for approximately 5 minutes or until part-cooked. Drain and set aside to cool.

Roll out the puff pastry on a lightly floured surface and trim to fit a 9-inch tart pan. Press the pastry into the pan, trimming any excess and crimping the edges.

Spread the caramelized onions evenly over the base of the pastry.

Arrange the sliced Jersey Royal potatoes in a circular pattern over the onions, overlapping slightly.

In a small bowl, whisk together the Jersey milk and egg to create an egg wash. Brush the edges of the tart with the egg wash.

Season with salt and pepper to taste.

Bake in the preheated oven for 20-25 minutes, or until the pastry is golden brown and the potatoes are tender.

If using seasonal local produce, blanch them lightly (if needed) and add to the tart as a garnish upon removing from the oven.

Garnish with fresh thyme leaves and serve warm.