Preheat the oven to 350° F. Grease and lightly flour a baking dish.
To make the cake: In a bowl whisk together the flour, salt and baking powder.
In a small pot heat the milk and butter, remove from the heat and set aside.
In a large bowl beat the eggs with an electric mixer on high speed for 2 minutes. Add the sugar and continue mixing for 5 minutes. Reduce the speed to low. Add the flour mixture, butter mixture, tangerine zest, vanilla extract and mix for 1 more minute.
Pour the batter into the baking dish and bake for 40 to 45 minutes or until a toothpick stuck in the middle comes out clean. Remove cake from the oven and with a fork make holes all over the top of the cake. Set aside to cool for 10 to 15 minutes.
When the cake is cooling, make the milk sauce, whisk together sweetened condensed milk, evaporated milk, heavy cream, tangerine juice and vanilla extract in a mixing bowl.
Pour the 3 milks sauce over the cake until it is all absorbed. Refrigerate for a least 3 hours or overnight before frosting.
For the frosting, in a small pot mix the water and sugar, over medium high heat, stirring constantly for 5 minutes. Set aside.
Beat the egg whites with cream of tartar until stiff peaks are formed. While beating the egg whites, add sugar syrup and continue beating for 5 more minutes. Add vanilla extract and beat 1 more minute. Spread the frosting over the cake and refrigerate until ready to serve.