In a heavy-bottomed saucepan, combine the sweetened condensed milk with evaporated milk. Cook over medium-low heat, stirring constantly with a wooden spoon to prevent sticking.

Continue cooking for 20-25 minutes until the mixture thickens and turns a light caramel color, coating the back of your spoon. Remove from heat.

In a separate bowl, lightly beat the egg yolks. Temper them by gradually adding a few tablespoons of the hot milk mixture while whisking constantly.

Pour the tempered yolks back into the saucepan, stirring continuously. Return to low heat and cook for 5-7 minutes until thickened to a custard consistency.

Stir in vanilla extract and a pinch of salt. Remove from heat and let cool slightly.

Divide the manjar blanco custard evenly among 8 serving glasses or ramekins. Refrigerate for at least 2 hours until completely chilled and set.

For the meringue, combine egg whites and granulated sugar in a clean metal bowl. Place over a pot of simmering water (double boiler method).

Whisk constantly until the sugar dissolves completely and the mixture reaches 160°F on a thermometer, about 3-4 minutes.

Remove from heat and beat with an electric mixer on high speed until stiff, glossy peaks form and the meringue cools to room temperature, about 5-7 minutes.

Gently fold in the port wine during the final minute of beating.

Transfer meringue to a piping bag fitted with a star tip. Pipe generous swirls of meringue on top of each chilled custard.

Dust lightly with ground cinnamon before serving.