Plum Cobbler

Ingredients

• 375 ml / 1 1/2 cups flour
• 30 ml / 2 tbsp sugar
• 1 pinch salt
• 125 ml / 1/2 cup cold unsalted butter, cut in pieces
• 1 egg yolk, beaten
• 30 ml / 2 tbsp cold water
• To taste sugar
• 1 kg / 2 lb plums, pitted and quartered
• 150 ml / 2/3 cup blackberries
• 150 ml / 2/3 cup raspberries
• 7 ml / 1 1/2 tsp ground allspice
• 2 envelopes vanilla sugar
• 30 ml / 2 tbsp cold butter