Bring water to boil into a medium pot.
Add the chopped chocolate and the coconut oil into a medium glass bowl, and place over the boiling water pot.
Let the chocolate and coconut oil melt, stirring frequently to combine.
Transfer into the blender, add the almond butter and erythritol, and pulse to combine.
Transfer back into the bowl and add the pistacchio, almonds, cranberries and raspberries, saving some for garnishing.
Line a 9x13' rectangle pan with parchment paper, and pour the chocolate mixture.
Top with the saved nuts, fruits and rose petals, then cover with plastic foil and freeze for an hour.
Remove from the freezer, cut and serve.