Pour the jar of cherries including syrup into a saucepan. Heat on medium until bubbly.
Mix the cornstarch with water in a small bowl until creamy. Pour into cherries and stir over heat.
Add cinnamon and vanilla. Stir frequently for 5 minutes until thickened, then turn off heat.
Pour the cherry filling into a 9" pie plate.
CRUMBLE TOPPING
Preheat oven to 350 degrees.
Cut a stick of chilled butter into cubes.
In a separate mixing bowl, stir the sugar, flour, cornstarch, baking powder and salt together.
Fold the butter into the dry ingredients and mix with a mixer or food processor until crumbly.
Using your hands, mix together to form the crumble. Sprinkle it over the cherries in the pie plate. Make sure to use it all.
Sprinkle the topping with a dusting of cinnamon.
Bake at 350 degrees for 45 minutes until crust is golden brown and cherries are bubbling.
Notes
Store leftovers in an airtight container in refrigerator for up to 5 days. Place Cherry Crumble in the oven to reheat and broil topping for a few minutes to crisp it up.
If using another type of cherries without syrup, you'll need to make a syrup with 1 cup of water and ½ cup of sugar to add to the filling. Mix in cornstarch as directed, and add cinnamon and vanilla.
It's not necessary to add extra sugar to the filling if using the original recipe since the syrup (or juice) contains sugar.