Skillet Brownie Sundae

Directions

To prepare the brownie, start by preheating the oven and making the brownies according to the brownie mix package directions.
To prepare the chocolate sauce, add the cream and half and half to medium sauce pot over medium heat (do this while the brownies are baking). Stir occasionally to prevent the cream from scorching. Once the cream begins to simmer, turn the heat to low or remove the sauce pot from the stove. Whisk in the dark chocolate. The mixture will look separated at first, but as the chocolate melts, it will start to come together as a smooth chocolate ganache. Keep warm until ready to use.
To top off the brownie and assemble the sundae, remove the brownies from the oven, when finished, and switch the oven to broil. Top the warm brownies with the mini marshmallows and chocolate chips, then crumble the graham crackers on top. Place the topped brownies back into the oven and broil 2–3 minutes, keeping a close eye and broiling just long enough to start melting the chocolate chips and lightly toasting the marshmallows.
Remove them from the oven and let the brownies cool just enough to cut. Cut into 9 squares.
For each sundae, start by preheating a small cast-iron skillet on medium-high heat for 3–5 minutes. Once hot, remove and place on a trivet or wooden cutting board. Place a brownie square in the middle of the cast-iron skillet, top with a scoop of vanilla ice cream, and pour on about 1/3 cup prepared chocolate sauce. The cast-iron skillet should still be hot enough to make the chocolate sauce bubble and sizzle.
Repeat with the remaining brownies or use multiple cast-iron skillets to enjoy simultaneously.