Preheat oven to 350 degrees Fahrenheit or 180 degrees Celsius. Spray a cake pan that is 9 by 13 with melted butter or oil using a pastry brush. Dust with gluten-free flour. In a mixing bowl, cream the butter and sugar with a hand blender or electric blender until light and fluffy Crack the eggs and pour the vanilla into your creamed mixture. Blend again, making sure there are no egg streaks in your creamed mixture. Add the baking powder, baking soda, xanthan gum, salt, and gluten free flour into a large bowl. Use a wooden spoon to combine the dry ingredients. Mix until well-combined. Pour half of the dry ingredients mixture into the creamed mixture. Blend on slow speed for about a minute, until there are no more flour streaks. Pour the rest of the dry ingredients and add only one-half of the milk. Blend on slow speed until the batter is mixed properly. When the cake batter has been combined well, pour the rest of the milk and mix again. The end result should be slightly stiff and glossy. Use a rubber spatula to scrape up all the cake batter into the cake pan. Place the cake pan into the oven. Have it bake for about 35 minutes, which is when the cake springs back when you touch it, and a toothpick comes out dry when you poke the cake. Flip the cake pan upside down on a wire rack. To make the cake easier to flip, circle a knife around it. It should pop out. Have the cake cool for about five minutes. the cake. Using your favorite frosting and icing, frost your cake to your liking. You can also add toppings such as sliced fruit, sprinkles, nuts, chocolate chips, and coconut flakes.

Summary:
Prepare to make the cake. Cream the butter and sugar. Add eggs and vanilla extract. Mix the dry ingredients in a separate bowl. Add half of the dry ingredients to the creamed mixture. Add milk and the rest of the dry ingredients. Pour the cake batter in cake pan. Bake the cake. Let the cake cool. Frost Enjoy!