Grind the Oreo cookies as finely as possible. Use a food processor or simply put them in a ziplock bag and beat them with a rolling pin until you have very fine cookie crumbs.
Meanwhile, melt the butter in a pan and stir in the cookie crumbs untill combined.
Line the cake tin with baking paper and pour the Oreo crumbs into it. Spread the mixture over the bottom and press down well. Place the cake tin in the refrigerator until further use .
Now heat the cream in a saucepan and break the chocolate into small pieces. Put the chocolate in a bowl and pour the hot whipping cream over the chocolate. Stir with a small whisk until the chocolate is dissolved in the cream. Finally, whisk in the butter.
Pour the chocolate ganache over the cookie base and put back into the refrigerator.
Let the chocolate ganache cake set overnight in the refrigerator and serve with fresh fruit.