To make the custard: place the milk in a small saucepan over medium heat and bring it to the boil.
Place the yolks, sticky rice flour and vanilla in a bowl and whisk to combine. Pour the milk into the egg mixture very slowly while whisking continuously to temper the eggs.
Pre-heat the oven to 200°C. Brush 4 ramkins with melted butter. Put 2 teaspoon of sugar in each ramkin an roll it around so that the sugar covers the buttered surfaces evenly. Tip out any excess sugar.
To make the meringue: In a bowl of a stand mixer, whisk the egg whites with a pinch of salt on low until frothy and add the sugar gradually then cream of tartare and continue whisking till it reach medium peaks.
In a large bowl, puree the bananas with a potato masher or a fork it should have some bits and not completely smooth. Whisk in the custard. Add 1/3 of the meringue and fold to lighten up the custard then add the rest and fold gently to combine.
Spoon the mixture into the prepared ramkins and fill half way through. Add 1 tbsp of dulce de leche and 1/4 of the crumbled graham crackers in each ramkin then fill with rest of the mixture. Smooth with a palette knife and tap gently to remove any trapped air.
Place the ramkins on a baking tray and bake for 10-15 minutes. Serve immediately.