Preheat your oven to 350°F (175°C).
Grease your 9x13 inch baking pan with butter or cooking spray.
In a mixing bowl, whisk together 3 cups of flour, 1 teaspoon of salt, 1 teaspoon of baking powder, and 1/2 teaspoon of baking soda. Set aside.
In a large mixing bowl, cream together 1 cup of softened butter and 2 cups of sugar until light and fluffy.
Beat in 4 large eggs, one at a time, until fully incorporated.
Gradually add the dry ingredient mixture to the butter-sugar mixture, alternating with 1 cup of buttermilk.
Pour the batter into the prepared baking pan, smoothing the top with a spatula.
Bake for 50-60 minutes, or until a toothpick inserted in the center comes out clean.
Prepare the glaze by melting 1/3 cup of butter in a saucepan. Stir in 3/4 cup of sugar, 2 teaspoons of vanilla extract, and 3 tablespoons of water. Bring to a boil, then remove from heat.
Once the cake is done, let it cool for about 10 minutes. Poke holes in the top and pour the warm glaze over the cake.
Let the cake cool completely before slicing and serving.
