A shortbread-like cookie base + raspberry lemon filling + crumble = an out of this world gluten-free, vegan treat! Perfectly balanced and a total crowd pleaser!
While the base bakes, combine the preserves, raspberries, and lemon juice in a small bowl and mash with a fork until well combined but some berry pieces remain.
Add the reserved dough, brown sugar, pecans, and oats to the mixing bowl used for the base. Using a mixer, pastry cutter, or your hands, mix until combined and "crumbly". Set aside.
Pour the raspberry filling over the hot cookie base and spread evenly. Sprinkle with crumble topping, pinching crumble with fingers to create tiny crumble "clumps". Do not press crumble into the filling.