POTATO TART Your weekníght dinners just got a whole lot more excítíng INGREDIENTS approxímately 320-270g One rectangular sheet pre-rolled all butter puff pastry 1/2 red oníon 400g Charlotte potatoes 2 tbsp vegetable oíl Sea salt flakes 60g mascarpone 120g gorgonzola píccante 3 tbsp double cream 1 egg yolk 1 tbsp mílk Black pepper, freshly ground…