Preheat the oven to 325°F. 

In a medium saucepan, whisk together the milk, sweetened condensed milk, sugar, cornstarch, egg yolks, vanilla and salt.

Cook over medium heat, stirring constantly, until the mixture comes to a simmer. Cook until it thickens, about 2 to 3 minutes, then remove the saucepan from the heat and let it cool slightly.

In a 9x13-inch baking pan, layer 1/3 of the pudding mixture on the base and add a layer of the vanilla wafers and bananas on top. Repeat this process 2 more times, until you have used up all the ingredients. Set aside.

In a medium mixing bowl, beat the egg whites with an electric mixer until they turn frothy.

Slowly add in the sugar and beat until it becomes fluffy, then add in the cream of tartar and beat until stiff peaks form.

Spread the meringue over the top of the banana pudding, sealing the edges to not overcook the bananas and creating small peaks with a spatula.

Bake for 25-30 minutes, or until the meringue peaks are golden brown. Let pudding rest for 5 minutes and then serve warm or refridgerate for 2 hours to chill if you prefer it cold.