Preheat the oven to 350˚F/175°C. Line 2 8-inch round baking pans (or you can use 3 6-inch round cake pans) with parchment paper or grease well with cooking spray.
In a large bowl, whisk flour, baking powder, baking soda and salt together to combine. Set aside.
In a large mixing bowl using an electric hand mixer (or stand mixer), beat eggs, oil, sugar and vanilla extract on medium speed for 6 minutes until thick, fluffy and light. Scrape the sides of the bowl if needed.
On a medium-low speed, slowly add the wet mixture to the dry mixture, mixing until just combined. Add in earl grey tea infused milk and mix until the batter becomes smooth. Avoid overmixing.
Divide batter evenly into your prepared cake pans, and bake on the center rack at 350˚F (175˚C) for 25-30 minutes, until the cake tester (or a toothpick) comes out clean. This means no wet batter remained in the cake.
Allow the cake to cook in cake pans for 10-15 minutes before transferring to cool completely on a wire rack. The cake must be cool completely or chilled in the fridge for at least 1 hour before applying frosting.