Place A Rack In The Center Of The Oven, And Preheat The Oven To 350°F.
Lightly Grease A 13″ × 9″ Baking Pan With The Vegetable Oil Spray Or Soft Butter.
Set The Pan Aside.
For The Cake, Place The Butter And Sugar In A Large Mixing Bowl, And Beat With An Electric Mixer On Medium Speed Until The Mixture Is Light And Fluffy, 1 To 2 Minutes.
Add The Eggs, One At A Time, Beating About 15 Seconds After Each Egg.
Blend In The Vanilla, And Set The Batter Aside.
Sift The Flour, Baking Powder, And Salt Into A Small Bowl.
Add The Flour Mixture To The Batter About 2 Tablespoons At A Time, Blending On Low Speed After Each Addition.
Pour The Batter Into The Prepared Pan, And Place The Pan In The Oven.
Bake The Cake Until The Top Springs Back When Lightly Pressed With A Finger And A Toothpick Inserted Comes Out Clean, 20 To 25 Minutes.
Remove The Cake To A Wire Rack, And Poke Holes On The Top Of The Cake With A Wooden Skewer.
Let The Cake Cool For 15 Minutes.
Meanwhile, Make The Milk Syrup.
Pour The Milks, Rum, If Desired, And Vanilla Into A Medium-Size Bowl And Stir.
Spoon The Syrup Over The Top Of The Cake, Letting It Soak Into The Holes.
Cover The Cake With Plastic Wrap, And Place It In The Refrigerator To Chill For 2 Hours.
For The Whipped Cream, Chill The Heavy Cream And The Beaters Of The Electric Mixer.
When Cold, Pour The Cream And Sugar Into A Large Mixing Bowl, And Beat On High Speed Until Stiff Peaks Form.
Remove The Cake From The Refrigerator And Spread The Whipped Cream Evenly Over The Top.
Return The Cake, Covered, To The Refrigerator Until Time To Serve.
To Serve, Cut Into Squares And Top With The Fresh Strawberries, If Desired.
