Preheat oven to 350°F. Mix flour, oats, brown sugar and butter until crumbly. Set aside 1 and ½ cups of this mixture and press the rest into a baking pan. Bake 15 minutes until lightly brown.
Beat Cream Cheese until fluffy. Gradually add condensed milk until smooth and stir in lemon juice. Spread on top of crumble layer in pan.
Stir blueberry sauce with corn starch and pour on top of cream cheese layer. Top with the remaining crumble.
Bake for 45 minutes or until golden brown. Once cooled cut into squares.
Serve warm with ice cream.
