Combine flour, sugar, baking powder, salt, cinnamon, and oatmeal in a large mixing bowl.
Using a fork, cut in the cubed butter until mixture resembles pea-sized crumbles.
In a small bowl, whisk egg, milk, and vanilla together.
Pour liquid ingredients over the flour mixture.
Whisk together until it resembles wet sand. Reserve 2 cups for topping.
Press remaining mixture into a greased 9x13 baking dish.
Combine ingredients for cranberry filling in a medium mixing bowl. Spread evenly over crust.
Evenly sprinkle remaining topping over cranberries.
Bake for 40-50 minutes or until the top is golden brown and a toothpick comes out clean.
Allow bars to cool.
For the Icing:
Drizzle melted white chocolate over top of bars and serve.
Notes
Balance Sweetness: Cranberries bring tartness to the recipe, so adjust the sweetness of the crumble topping and filling accordingly to achieve a harmonious balance of flavors.Texture Matters: Ensure the crumble topping is crispy and the cranberry filling is thickened to prevent the bars from becoming soggy. A good texture contrast adds to the overall enjoyment.Experiment with Spices: Enhance the flavor profile by adding spices like cinnamon or nutmeg to the crumble topping. These aromatic spices can complement the tartness of the cranberries beautifully.