Preheat the oven to 350°F (175°C). Grease or spray a standard loaf pan with non-stick cooking spray.
Cream butter and sugar
In a large mixing bowl, cream together the softened butter and granulated sugar until light and fluffy. Add the milk, eggs, and vanilla extract, mixing thoroughly until smooth.
Combine dry ingredients
In a separate bowl, whisk together the baking powder, salt, and flour. Gradually add the dry mixture to the wet mixture, stirring until just combined. Avoid over-mixing.
Add apples and walnuts
Fold in the diced green apples and chopped walnuts until evenly distributed. Spread the batter into the prepared loaf pan.
Prepare the topping
In a small bowl, combine the flour, brown sugar, granulated sugar, and ground cinnamon. Add the cubed cold butter and cut it into the mixture with a fork until coarse crumbs form. Sprinkle evenly over the batter.
Bake
Bake for 50–60 minutes, or until a toothpick inserted into the center of the bread comes out clean. Allow the bread to cool in the pan for several minutes before transferring to a wire rack.
Glaze the bread
In a small bowl, whisk together the melted butter, confectioner’s sugar, vanilla extract, and milk until smooth. Drizzle the glaze evenly over the cooled bread before slicing and serving.
Notes
To make this Dutch Apple Bread gluten-free, substitute the all-purpose flour in both the bread and topping with a 1:1 gluten-free baking blend. Ensure the baking powder and confectioner’s sugar used are certified gluten-free.