FOR THE CRUMB TOPPING: – 1/2 cup (60g) all-purpose flour – 1/4 cup (50g) firmly packed light brown sugar – 1/2 teaspoon ground cinnamon – 1/4 teaspoon salt – 3 tablespoons (42g) unsalted butter, softened – 3 tablespoons sliced almond FOR THE CAKE: – 1 & 1/2 cups (180g) all-purpose flour – 1/2 cup (48g) almond flour – 1 teaspoon baking powder – 1/2 teaspoon salt – 1/2 cup (113g) unsalted butter, softened – 3/4 cup (150g) granulated sugar – 2 large egg – 1 teaspoon almond extract – 1/2 cup (118ml) milk – 1/4 cup (56g) sour cream