Spray a 9 x 13 inch baking dish with cooking spray and set aside. Cut the bagels into 1-inch pieces.
In a large mixing bowl, whisk together the evaporated milk, sweetened condensed milk, eggs, vanilla, salt and nutmeg. Pour this mixture over the bagel pieces and press the pieces gently into the custard.
Fold the blueberries and 3/4 cup of white chocolate chips into the bread pudding by hand, then pour evenly into the prepared baking dish. Cover and chill overnight.
Preheat the oven to 375°F. Uncover and sit on counter for 20 minutes while oven preheats. Bake for 38-40 minutes or until the top is golden brown. Let stand for 15 minutes before serving.
Meanwhile, in a microwave safe bowl, melt together white chocolate chips with cream. Heat in 20 second increments stopping to stir each time. Repeat until smooth. Mix in powdered sugar stir until smooth.
Drizzle bread pudding with glaze and sprinkle toasted almond slices on top. Serve warm.
After glazing the bread pudding, let it rest for 5-10 minutes before serving. This will allow the flavor of the glaze to soak into the bagels.