3 delicious cake streusel Recipes

all purpose flour, golden brown sugar, chopped walnuts, salt, unsalted butter, melted, golden delicious apples, peeled, halved, cored , cut into 1/8-inch-thick slices, ground cinnamon, cake flour, cornstarch, baking powder, salt, unsalted butter (2 1/4 sticks), room temperature, powdered sugar, grated lemon peel, vanilla bean , split lengthwise, eggs plus 1 large egg yolk

brown sugar, ground ginger, ground cinnamon, all-purpose flour, unsalted butter, chopped walnuts, all-purpose flour, ground ginger, ground nutmeg, baking powder, baking soda, salt, crystallized ginger, finely chopped, unsalted butter, at room temperature, dark brown sugar, sugar, vanilla extract, eggs, buttermilk, granny smith apples or 1 medium golden delicious apple, cored and chopped coarse, sugar (for dusting)