Blackberry Peach Galette

Bahan-bahan (8 porsi)

• 1 cup fresh blackberries
• 1/4 cup brown sugar
• 1 tablespoon cornstarch
• 2 teaspoons vanilla extract
• 1 sheet frozen puff pastry, thawed
• 1 -2 peaches, thinly sliced
• 2 tablespoons honey or pure maple syrup
• 2 tablespoons salted butter
• 1 egg, beaten
• coarse sugar, for sprinkling