Prepare Pan: Preheat oven to 350°F (175°C). Spray a 9x13 inch baking pan with nonstick cooking spray.

Mix Dry Ingredients: In a large bowl, whisk together flour, baking powder, and salt. Set aside.

Separate Eggs: Separate the eggs, placing yolks in one bowl and whites in another. Use cold eggs for easier separation.

Beat Yolks: Add 3/4 cup sugar to the egg yolks. Beat with an electric mixer on high speed until pale yellow, about 2 to 3 minutes. Add 1/3 cup whole milk and vanilla, stirring to combine.

Combine with Flour: Pour egg yolk mixture over flour mixture and stir gently just until combined.

Whip Egg Whites: Using clean beaters, beat egg whites on high speed until soft peaks form, about 1 minute. Gradually add remaining 1/4 cup sugar while mixing on medium-low, then beat on high until stiff peaks form.

Fold Gently: Using a rubber spatula, gently fold the whipped egg whites into the batter just until combined. Do not deflate the whites.

Bake: Pour batter into prepared pan and spread evenly. Bake for 25 to 35 minutes, or until a toothpick inserted in the center comes out clean. Cool completely on a wire rack.

Make Milk Mixture: In a large measuring cup, combine evaporated milk, sweetened condensed milk, and 1/4 cup whole milk. Whisk until smooth.

Soak Cake: Once cake is completely cool, use a fork to poke holes all over the surface. Slowly pour milk mixture over entire cake, starting at edges and working toward center. Cover and refrigerate for at least 1 hour or overnight.

Make Whipped Topping: Beat heavy whipping cream, 3 tablespoons sugar, and 1/2 teaspoon vanilla on high speed until stiff peaks form.

Finish: Spread whipped cream evenly over chilled cake. Dust with ground cinnamon and garnish with fresh strawberries if desired. Serve chilled.