Preheat oven to 350 degrees F. Line a bread pan with parchment paper or spray with non-stick cooking spray.
Cream butter and sugar in a mixing bowl. Add in eggs, milk and vanilla and stir to incorporate. Mix in flour, salt, cinnamon, nutmeg and baking powder. Fold in apples. Transfer mixture to prepared baking pan.
Topping:
Combine all ingredients and mix with a fork or pastry mixer until crumbly. Sprinkle over batter in pan.
Bake for 55-60 minutes, until toothpick inserted in bread comes out clean. (Internal temperature of bread will be 200 degrees F when fully cooked.) Let cool. Remove from pan.
Glaze:
Whisk glaze ingredients together until smooth and drizzle over top of bread. Slice and serve.