Preheat your oven to 350°F (175°C). Grease and flour an 8-inch round cake pan.
In a bowl, whisk together flour, baking powder, and salt.
In a large bowl, beat butter and sugar until light and fluffy. Add eggs one at a time, beating well after each addition.
Mix in orange juice, milk, orange zest, and vanilla extract.
Gradually add dry ingredients to wet mixture, mixing just until combined. Avoid overmixing.
Pour batter into the prepared cake pan. Bake for 25–30 minutes, or until a toothpick inserted in the center comes out clean.
Let the cake cool in the pan for 10 minutes. Transfer to a wire rack to cool completely.