Preheat the oven to 350 F.
Mix the melted butter with the ground up chocolate graham crackers.
Divide between two tart pans and press down, and on the sides, using fingers or a flat bottom glass or a cup.
Place on an oven safe dish (for easier moving in and out of the oven) and place in the oven.
Bake for 20 minutes.
When finished, take tart shells out of the oven, and let cool completely before filling.
Melt the chocolate in the microwave in 20 second increments, whisking after each session.
Heat the cream over medium heat and bring to a simmer (just before boil).
Remove from the heat, and pour cream over melted chocolate. Add a pinch of salt (about 1/8 tsp) and mix really well.
Divide the mix between two tart shells, sprinkle with flaky salt, and place in the refrigerator to chill.
If adding raspberries and/or mint leaves, place them on top (anywhere you like) halfway through the chilling time. So, if you only have an hour, set a timer for 30 minutes. If you have two hours, set it for an hour.
When fully chilled, serve immediately after removing from refrigerator. Otherwise, keep in an airtight container for up to two days. To remove the outer ring of the pan, pop the bottom up and out. Then, using a knife, very carefully separate the bottom lining of the pan from the actual tart. Enjoy!