In a medium saucepan combine sugar and orange juice and bring to boil. When it starts simmering, lower the heat and add the cornstarch, dissolved in the water. Mix continuously to avoid burning. When the mixture starts to thicken, remove from heat, cover with a lid and let cool for 30 minutes.
In a bowl combine the biscuit crumbs and the ground almonds and stir to blend. Spoon the mixture evenly into 4 glasses or small jars.
In a large bowl beat the cream cheese and the powder sugar until combined.
In a separate bowl whip the cream. With a rubber spatula fold it carefully into the cream cheese mixture.
Spoon evenly the cheese filling onto the biscuit base. Top with the cool orange topping.
Cover the glasses with cling film and transfer to the fridge for 6-8 hours.
Decorate with fresh orange slices right before serving.
Alternatively the topping could be prepared with processed orange pulp instead of juice only. Keep in mind that this way the topping would be slightly bitter and its consistency might not be completely smooth.