Raspberry Filling

1. In a medium saucepan combine the raspberries first with the sugar and cornstarch, and then juice of the lemon. Stir to coat. Place over medium heat and stir occasionally. After about 5 minutes, the mixture will start to steam and bubble. Stir continuously for another 3 to 5 minutes or until the mixture is thickened and glossy, like raspberry jam.
2. Pour into a wide and shallow dish and allow to cool in the refrigerator while we prepare the rest of the layers.

Cream Cheese Filling

1. In a medium bowl, mash and mix together the cream cheese and sugar using a fork. Mash in the vanilla and egg, then switch to a whisk to mix smooth and creamy. Set aside.

Crumble

1. Preheat the oven to 350F and grease the inside of a 9×13 baking dish. Line the bottom and two longest sides with parchment paper with some overhang for easy removal.
2. Add the brown sugar, sugar, flour, salt and baking powder to a large bowl. Use your hands to mix and toss together, breaking up any brown sugar lumps as you go. Use a silicone spatula to stir in the butter. Spend a good couple minutes to ensure the mixture is evenly hydrated and no dry patches remain. It should appear moist but very crumbly. 
3. Press about ⅔ of the crumble into the bottom of the pan into a thin layer all the way to the edges. Spread the cream cheese on top in an even layer. Spoon the raspberry filling over top and spread even, careful not to disrupt the cream cheese underneath. Break up the crumble and sprinkle it evenly over the surface, nearly covering the raspberry filling.
4. Bake for 35 to 40 minutes or until the edges are golden, the surface appears dry, and the center tightly jiggles when the pan is nudged.
5. Allow the bars to cool at room temperature for about 20 minutes, then transfer to the refrigerator to cool completely, about 2 hours. Once chilled, lift the bars out, slice into 12 large squares, and enjoy!