<p>Preheat oven to 350°F (175°C). Grease and flour a cake pan.</p>
<p>In a large bowl, mix flour, sugar, and cocoa powder together. Add eggs, milk, oil, and vanilla and mix until smooth.</p>
<p>Pour the batter into the prepared pan and bake for 30-35 minutes or until a toothpick inserted into the center comes out clean. Let cool before serving.</p>