Plum Galette with Streusel Topping

INGREDIENTS

• 1 teaspoon ground cinnamon
• 1 pound short crust pastry, recipe follows
• Refrigerate the pastry rounds for at least 30 minutes. Cut 5 evenly spaced 1-inch slits around the edge of each pastry round (perpendicular to the edge).
• For the pastry: Roll the short crust pastry 1/4-inch thick and cut into 6 (6-inch) rounds.
• Special equipment: rolling pin
• 1/3 cup brown sugar
• 1/2 teaspoon ground cardamom
• 6 purple plums, pitted and thinly sliced
• 1 egg yolk
• 1/4 cup sugar
• 2 tablespoons water
• 1/2 cup unsalted butter, cold
• Preheat the oven to 425 degrees F.
• 1 cup all-purpose flour