Place fruit in a large bowl and sprinkle over the lemon juice, gently toss.
In a medium bowl, mix the sugar and cornstarch.
Sprinkle sugar and cornstarch mixture on top of the fruit and toss to coat. Set aside for 15 minutes.
Remove dough from the fridge and roll out on a piece of parchment to a 12-14" circle, about 1/3" thick. It’s ok for the edges to look uneven and rustic.
Gently transfer the rolled dough on parchment to a baking sheet.
Brush the center of the dough, about 2" from the edges with beaten egg and evenly spread the almond flour on top.
Spread the fruit on top of the almond flour with some of the liquid.
Gently fold the edges of dough over the fruit.
Brush with egg wash, sprinkle with the flaked almonds and place in the refrigerator for about 45 minutes.
Preheat to 425°F with the oven with the rack in the middle position
.
Bake for 25-30 minutes or until the crust is golden brown and the juices are bubbling.
Remove from oven and allow to cool slightly before slicing. Serve with vanilla ice cream.