In a small bowl combine the unflavored gelatine with 50 ml. water and let bloom for 5 min.
Cut the strawberries into chunks and place in a large saucepan. Blend them with the hand blender until smooth.
On medium heat, bring the strawberry puree to a boil stirring occasionally. Reduce the heat to low and simmer for about 2 minutes.
Remove from the heat, add the bloomed gelatin and stir until melted. Set aside to cool.
In the mixer bowl or another small bowl whisk the chilled cream with stevia until stiff peaks form.
In a large bowl, whisk together the greek yogurt and evaporated milk using a hand whisk or mixer.
Pour the strawberry puree (it should be slightly warm) to the bowl with greek yogurt and evaporated milk mixture. Whisk to combine.
Add the whipped cream and gently mix together with a spatula. Be careful not to over-mix!
Assemble the cake. Place the cake layer into the bottom of the 8-inch diameter springform pan and line the sides with acetate or parchment paper (optional).
Pour the strawberry mousse mixture into the springform over the cake layer and spread evenly. Refrigerate for 4 hours or overnight.