1Preheat your oven to 350°F (175°C) and grease a 9-inch round cake pan.
In a large mixing bowl, sift together the whole wheat flour, cocoa powder, baking powder, and salt.
In another bowl, mix the sugar, milk, vegetable oil, and vanilla extract until well combined.
Gradually add the wet ingredients to the dry ingredients, stirring until just combined. Be careful not to overmix.
Pour the batter into the prepared cake pan and smooth the top with a spatula.
Bake in the preheated oven for 30-35 minutes, or until a toothpick inserted into the center comes out clean.
Allow the cake to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before serving.