Start with the crust. Pulse the cookies in a food processor into coarse, rough bits. Add in the butter and pulse until the cookies are a fine crumb and the butter incorporated. Press this into a 9" - 10" fluted tart pan and set in the fridge for at least 1 hour.
Make the chocolate glaze by melting the chocolate and coconut oil together in a small liquid measuring cup by microwaving in 15 second intervals. Stir the mixture after each interval and once the chocolate is about 75% melted let it sit for a few seconds, letting the residual heat melt the rest of it through. Let it sit on the counter for a few minutes to cool just a bit. Pour the glaze onto the tart and brush it evenly across the bottom and around the sides. Sit this in the fridge for another to let the glaze firm up.
To make the filling melt the mini marshmallows, butter, whole milk, and sugar in a saucepan over medium-low heat until you have a melted, marshmallowy paste. Stir in the creme de menthe, mint extract, and green food dye. Set aside to cool a bit.
Once the marshmallow stuff is room temperature—it doesn't need to, and in fact shouldn't, be cold but it shouldn't be warm either as it will melt the cream—beat the cream cheese into the mix with a hand mixer.
Whip the cream to medium peaks in a separate bowl. Plop about 1/4 cup of the whipped cream into the base and stir in to lighten the marshmallow mix—this will make it easier to fold the whipped cream in. Speaking of which, fold in the whipped cream. Decant this into the chilled crust, smooth over the top, and chill for at least 2 hours, preferably 6 - 8.
Serve with extra whipped cream or shaved chocolate or crushed cookies on top.