Preheat oven to 425°.
Line a jelly roll pan with foil; coat foil with cooking spray. Roll dough to a 14-inch circle on a lightly floured surface. Place dough on prepared pan. Roll marzipan to a 9-inch circle on a lightly floured surface. Place marzipan on top of dough.
Combine apple, 1/2 cup sugar, flour, 3/4 teaspoon almond extract, juice, and salt in a large bowl; toss well. Spoon apple mixture over marzipan. Fold 2-inch dough border over the apple mixture, pressing gently to seal (dough will only partially cover apple mixture). Bake at 425° for 30 minutes or until lightly browned (apple filling may leak slightly during cooking).
Place 1/4 cup sugar in a small heavy saucepan over medium-high heat; cook until sugar dissolves, stirring as needed to dissolve the sugar evenly (about 4 minutes). Cook 1 minute or until golden. Remove from heat; carefully stir in 1/4 teaspoon almond extract. Drizzle over galette.