Preheat the oven to 325°F.
In a saucepan, combine the cream and milk. Bring to a near boil. Add the shredded coconut. Turn off the heat immediately and add the vanilla chips. Using a spatula, keep stirring until the chocolate is fully incorporated (see tips). Strain the dairy liquid through a fine mesh sieve in a bowl to remove the coconut solids.
In a mixing bowl, whisk the egg yolks with superfine sugar until they become pale yellow. Add the banana and rum extracts and salt.
Combine the dairy liquid with the egg mixture by slowly adding a ladle of the dairy liquid at a time to prevent the yolks from curdling (it’s called tempering).
Strain one more time through a fine mesh and discard all the solids (if any).
Fill the 6 (2-ounce) ramekins with the crème brulée custard. Place them in a warm water bath in a deep baking pan. The water should go half-way up the side of the ramekins (at least a 1-½-inch-high level of water). Loosely cover the dish with a sheet of aluminum foil and place in the oven for 30-35 minutes. The texture of the crèmes brulées should be a little jiggly but not liquid (the custard will get firmer and creamier as it chills in the refrigerator).
Allow the crèmes brulées to cool completely first, then plastic-wrap each individual cup and chill in the refrigerator for at least 3 hours. The fat from the cream may pick up other food odors from the refrigerator if the cups are not sealed properly.
For the bananas: Peel and slice the bananas. Coat them with lemon juice to prevent them from browning. Place the sliced bananas in a small pan over high heat. Sprinkle with the granulated sugar and cook until all the bananas are coated on both sides and caramelized but still firm enough.
When serving, unwrap the cups and sprinkle about 1 teaspoon of sugar in each cup, then caramelize with a culinary torch.
Garnish the crèmes brulées with the bananas. Sprinkle with toasted coconut flakes and finish with a fresh mint leave.