Preheat the oven to 375 degrees Fahrenheit.
Spray a jelly roll pan (15x10inches) with nonstick spray.
In a large bowl combine the flour, sugar, baking soda and salt. Whisk together.
Add your butter and water to a sauce pan and bring to a boil over medium high heat.
Remove from heat and pour into the flour mixture. Stir until combined.
Add in the eggs, sour cream, and vanilla extract and stir it all together.
Pour cake batter into the prepared pan.
Bake the cake for 18-23 minutes, or until a toothpick inserted in the center comes out clean (a few crumbs are okay).
Cool the pan for 20 minutes.