Preheat Oven: Start by preheating your oven to 350°F (175°C) and grease a baking dish.
Combine Dry Ingredients: In a bowl, mix together 1 cup of sugar, 1/2 cup cocoa powder, 1/4 cup flour, and 1/4 teaspoon of salt until well-blended.
Whisk Wet Ingredients: In a separate bowl, whisk together 2 cups of milk, 4 large eggs, 1 teaspoon vanilla extract, and 1/4 cup melted butter until smooth.
Combine Mixtures: Pour the wet mixture into the dry mixture and stir until just combined. The batter will be quite thin.
Bake: Pour the batter into the prepared baking dish and bake for 40-45 minutes or until set. You can test doneness by inserting a toothpick into the center—it should come out clean or with just a few moist crumbs.
Cool and Serve: Allow the cake to cool slightly before serving. Dust with powdered sugar or pair with ice cream for extra sweetness.