Place layers of paper towels (about 5 deep) on a waterproof surface. Spread the yogurt out on top. Leave it for 15 minutes, checking occasionally. If the paper towels become soaked through remove them and add a few sheets of fresh dry ones. When the yogurt has thickened considerably, it is ready to add to the recipe.
In a separate bowl, mix together the strained vanilla yogurt and the egg.
Spread the cream on top of the Oreos and distribute the fresh raspberries over the top.