Process the cookies into crumbs in the food processor. If you don't have a food processor, put them in a plastic zipper bag and beat the hell out of them until they turn into crumbs. Mix the crumbs with the butter in a bowl. Press the crumbs into a 9 or 10 inch tart pan, preferably one with a removable bottom. Chill for at least 30 minutes.
In another bowl, combine the cream cheese, mascarpone, sugar and dulce de leche. Beat on medium speed until well-blended, about 2 minutes. Pour filling into tart shell and chill for at least 2 hours.
.Meanwhile, toast the coconut by heating it in a small skillet over medium to medium-high heat, tossing it often so it doesn't burn. When the coconut is golden brown remove from heat and set aside to cool.
When tart is thoroughly chilled, spread the remaining cup of dulce de leche over the filling, gently spreading it to cover. Be careful not to mush the filling. Spread the toasted coconut over the dulce de leche and drizzle with the melted chocolate.
Hang on to your socks while eating, so as not to knock them off!