Creating White Texas Sheet Cake is straightforward when you follow these simple steps:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease and flour a large sheet cake pan.
2. Mix Dry Ingredients: In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
3. Cream Butter: In another bowl, beat the softened butter until creamy.
4. Combine Ingredients: Gradually add the dry mixture to the butter, alternating with buttermilk. Mix until smooth.
5. Add Eggs and Vanilla: Beat in the eggs and vanilla extract until fully incorporated.
6. Pour Batter: Pour the batter into the prepared sheet pan, spreading it evenly.
7. Bake: Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted in the center comes out clean.
8. Cool the Cake: Allow the cake to cool in the pan for about 30 minutes before transferring it to a wire rack.
9. Prepare the Frosting: In a medium bowl, cream the butter for the frosting until smooth. Gradually add powdered sugar, milk, and vanilla, mixing until creamy.
10. Frost the Cake: Once the cake is completely cool, spread the frosting evenly over the top.

These steps will guide you seamlessly through the process of making this incredible cake.