Coat a 9X13 baking dish with unsalted, room temperature butter. Cube the King's Hawaiian rolls and place in a mixing bowl.

In a separate mixing bowl, whisk together whole milk, eggs, vanilla extract, cinnamon and nutmeg. Pour it through a sieve into another mixing bowl with the lemon zest and blend to combine. Pour the milk egg liquid over the cubed bread and toss to coat.

Layer half the bread mixture at the bottom of the prepared baking dish, followed by half the blueberries. Arrange them in an even layer. Repeat layers and pour any remaining liquid over the dish. Cover with plastic wrap and refrigerate overnight. Don't press down as you don't want to compact the fluffy cubed bread.

Make the crumb topping by whisking together flour, sugar, cinnamon, nutmeg and a tiny pinch of salt in a small bowl. Using your hands cut the cubed butter with the flour mixture until it is coarse and crumbly, about the size of small peas. Place the crumble in a Ziploc bag and refrigerate along with the casserole.

In the morning, preheat the oven to 350°F and remove the casserole from the refrigerator. Remove the plastic wrap and spread the crumb topping evenly over the casserole. Bake for 35 - 40 minutes or until golden brown. Allow to cool and set for 5 minutes before serving.

Garnish with a extra lemon zest and dust with powdered sugar. Serve it with maple syrup.