To Make the Blueberry Filling

1. Stir together the sugar, cornstarch and salt in a large saucepan. Whisk in the water until everything has dissolved, over medium-low heat.
2. Bring the mixture to a boil over medium-high heat, stirring regularly. Reduce the heat slightly and simmer for 2 minutes.
3. Add the blueberries and increase the heat to medium-high, allowing the blueberries to release their juices. Continue heating and stirring, allowing the mixture to boil a little and thicken for about 8-10 minutes. Remove pan from heat and let mixture cool.
4. Refrigerate filling in an airtight container for 4-6 hours to thicken. Store in the refrigerator for up to 2 weeks.

To Make the Cheesecake Pie with Crumb Topping

1. Preheat the oven to 375°F. Spray a 9-inch deep dish pie plate with non-stick baking spray.
2. Place the pie crust in the pie plate. Fold the edges of the crust under and mold them to your preference. Refrigerate until ready to use.
3. To make the cheesecake layer, beat the cream cheese until creamy.
4. Add the sugar and beat the mixture until smooth.
5. Add the egg and beat until full incorporated. Do not overbeat the batter.
6. Spread the cheesecake batter in the prepared pie crust.
7. Gently spoon the blueberry filling on top of the cheesecake batter.
8. For the crumb topping, mix together the crumb topping ingredients. Sprinkle the mixture evenly over the blueberry filling.
9. Bake the cheesecake pie for 40 minutes.
10. Remove the pie plate from the oven and place it on a wire rack. Let the cheesecake pie cool for 1 hour, then refrigerate for 2-3 hours, until completely chilled.
11. Serve with vanilla ice cream and a sprinkle of cinnamon, if desired.