Preheat the oven to 350 degrees.
In a bowl combine the gluten-free flour, xanthan gum, baking powder, and salt.
In another bowl mix together egg yolks and 3/4 cup sugar. Mix until the yolks are pale yellow. Stir in the vanilla and milk. Fold in the flour mixture until combined. Be careful not to over mix the batter.
In a stand mixer using the whisk attachment, beat the egg whites until soft peaks form. Add the remaining 1/4 cup sugar and continue mixing until stiff peaks form.
Gently fold the egg whites into the batter. Be sure to scrape the bottom and sides of the bowl. Mix until well combined.
Pour into an ungreased 7-inch x 11-inch rectangle baking pan (approximately 3 quarts capacity). Bake for 30-35 minutes, until an inserted toothpick comes out clean. Remove from the oven and place on a wire rack to cool. Allow the cake to cool completely.
Use a fork to poke holes all over the top of the cake.
Make the milk mixture by combining the evaporated milk, sweetened condensed milk, and whole milk. Pour over the top of the cake. Be sure to pour near the edges and all around the cake.
Refrigerate the cake for a minimum of one hour or overnight.
After the cake has soaked up the milk mixture, make the whipped topping.
In a stand mixer with the whisk attachment, whisk together the heavy cream, sugar, and vanilla until stiff peaks form.
Smooth the whipped topping over the top of the cake.
In a mesh top shaker, mix the cinnamon and powdered sugar together. Shake over the top of the whipped topping. Top with strawberries and serve.