(Prepare before baking the cake or while it’s in the oven.)
In a medium saucepan, add sweetened condensed milk, evaporated milk and whole milk. Mix well and cook over medium heat, 8-10 minutes. (Do not bring to a boil.)
Set aside to cool. After it’s cooled, add Florida orange juice and mix together. Set aside until needed.
For orange vanilla cake
Heat oven to 350 degrees F. Generously spray a 9-inch square pan with nonstick baking spray on the inside bottom and sides. Set it aside.
Sift the flour and baking powder into a medium-sized mixing bowl. Set aside.
In a large mixing bowl, add butter and sugar. Cream the butter and sugar using an electric hand mixer, until fluffy, about one minute. Add the eggs, vanilla extract and Florida orange juice to creamed butter mixture. Beat 1-2 minutes, until well mixed.
Add the flour mixture in batches, about 1/2 at a time. Mix until blended with a rubber spatula, but don’t overmix.
Pour batter into prepared pan and level out the top with your spatula.
Bake for 20 to 21 minutes at 350 degrees F, until a toothpick inserted in the center comes out clean.
Remove cake from the oven and place on a cooling rack. Cool the cake for at least 30 minutes to an hour.
For whipped cream
Add heavy cream, powdered sugar, and vanilla to a large mixing bowl (with high sides). Whip using an electric hand mixer, 5 to 6 minutes, until soft peaks form.
To assemble
Poke holes all over the cake with a fork. Make sure you poke holes all over the cake!
Slowly pour the cooled orange-milk soaker mixture about 1/4 of the mixture at a time, allowing the soaker to be absorbed each time. You can use a rubber spatula to spread it and gently push the soaker into the cake. Repeat until finished.
Allow the cake to sit and absorb the soaker for 45 minutes to an hour (on your counter). (This is an important step. The cake needs to absorb the milk and orange juice before you refrigerate it.)
Cover cake with plastic wrap and refrigerate cake for at least one hour. Remove and frost with whipped cream as desired. The cake is now ready to serve.