Make the candied oranges first. In a large skillet, heat ¾ cup of water and 1 cup of sugar until the sugar is dissolved and the mixture begins to boil. Slice one Satsuma (or similar mandarin orange) into ⅛ inch slices and add to the hot syrup. Cook the orange over a simmer, covered, for 30 minutes. Cool the oranges on a wire rack and pour the orange simple syrup into a jar. Pop the jar into the refrigerator for later use.
Next, preheat an oven to 325° F. Make the tart shell. Add the chocolate graham crackers to a large food processor and chop into a fine crumb. Add the sugar and slowly drizzle in the melted butter. Pulse until the crumb mixture starts to come together.
Press the chocolate graham cracker mixture into a 10-inch tart shell using your fingers or the back of a measuring cup. Bake the shell for 12 minutes, then let cool on the counter.
While the tart shell cools, make the tart filling. Increase the oven temperature to 350°F. Chop the bittersweet and unsweetened chocolate and add to a large bowl. Heat 1½ cups of heavy cream in the microwave until very hot, but not boiling. I do this in 30 second increments so as not to overheat the milk.
Pour the hot cream over the chocolate and let sit for 3 minutes before stirring. Stir until smooth, then add the remaining ingredients: vanilla extract, orange extract, orange zest, reserved orange simple syrup, salt and eggs. Whisk until smooth, then pour the filling into the pre-baked tart shell. Bake the tart at 350° F for 22-25 minutes or until the sides are set, but the middle of the tart is still a little wobbly. Cool the tart on the counter for 10 minutes, then pop it into the refrigerator to cool for an additional hour.
When the tart is cooled, make the ganache. Add ¾ cup of chopped dark chocolate to a bowl along with a pinch of kosher salt. Heat 1 cup of heavy cream in the microwave until very hot, but not boiling. I do this in 30 second increments so as not to overheat the milk. Pour the hot cream over the chocolate and let sit for 3 minutes before stirring. Stir until smooth.
Pour the ganache over the top of the tart until the ganache reaches the very top of the tart. You may have a few tablespoons of ganache leftover. Mix it with hot milk and enjoy some hot cocoa. Pop the glazed tart back into the refrigerator to set for another hour. Garnish the tart with the reserved candied oranges, then refrigerate the tart for at least one hour longer before slicing and serving. Enjoy!
