First, be safe: tie your hair back, roll up long sleeves, keep a large lid handy and a fire extinguisher handy too, if you have one.
Pour the coconut rum, if using, and the spiced rum into separate bowls. Never pour alcohol into the hot pan straight from the bottle or the whole thing could go up in flames. Be prepared!
Have four bowls of ice cream ready to go.
Place a medium stainless steel skillet over medium-high heat. Add the butter, brown sugar, a pinch of kosher salt, cinnamon stick, cloves and cardamom pod. Stir until a sauce forms.
Place the bananas cut-side down in the sauce and cook until caramelized, about 2 minutes each side. If desired, pull the cinnamon stick, cloves and cardamom pod from the pan now.
When the sauce starts to foam, pull the pan off the heat and sprinkle in the coconut rum. Return the pan to the heat and cook for 30 seconds.
Once again pull the pan off the heat and pour the spiced rum into the pan. Using a long gas lighter, light the contents of the pan away from the heat; it should immediately light up. Return the pan to the heat, reduce the heat to a simmer and cook until the flames go out.
Place two pieces of banana in each bowl of ice cream and divide the sauce among the bowls. Sprinkle with the coconut flakes and a little sea salt over the top and serve!