Process the graham crackers and brown sugar (if using) into fine crumbs. You can use a food processor or a zip-top bag and a rolling pin.
Add melted butter and mix until combined.
Stand the mango on a cutting board and slice both sides slightly off-center, avoiding the pit. Scoop out the flesh with a spoon.
Purée 4 mangoes in a food processor or mash with a fork.
Thinly slice the other 2 mangoes to use as the topping.
Using a stand or hand mixer, whisk cream cheese and condensed milk together until smooth.
Add heavy cream and whisk until thick and fluffy. Do not overmix.
On the bottom of your dish, press half of the graham mixture using a ramekin or a glass.
Spread half of the stabilized whipped cream using a spatula or a spoon.
Place half of the mango purée on top.
Add the rest of the graham crackers, then the rest of the whipped cream mixture.
Top it off with mango slices. Refrigerate for a few hours before serving.
Notes
Mangoes: Use Manila or Ataulfo mangoes. If not available, use Haden or Kent varieties.
Graham crackers: Broas or ladyfingers are an excellent substitute; they will soften into a cake-like texture. Nilla wafers, digestive cookies, or anything similar can also be used.
Heavy cream: You can also use shelf-stable Nestlé table cream or all-purpose cream. Refrigerate before whipping to get a thicker consistency.
Cream cheese: It stabilizes the whipped cream mixture, making it thick and creamy. Soften to room temperature before mixing to prevent lumps.