Preheat your oven to 350°F (175°C) and then grease and line two 8-inch cake pans with parchment paper.

In a small saucepan, heat the milk over medium heat until it barely steams. Remove it from the heat and add the Earl Grey tea bags and lavender buds. Steep for 5 minutes, then strain out the tea bags and lavender, reserving the infused milk.

In a bowl, whisk together the flour, baking powder, baking soda, and salt until well combined.

In a mixing bowl, cream 1/2 cup of the softened butter with the granulated sugar until light and fluffy, about 3-5 minutes.

Add the eggs one at a time, mixing well after each addition. Mix in sour cream and 1 tsp of vanilla extract until smooth.

Alternately add the dry ingredients and the tea-infused milk to the butter mixture, beginning and ending with the dry ingredients. Mix just until combined; it's okay if there are a few small lumps.

Divide the batter evenly between the prepared pans and bake for 25 to 30 minutes, or until a toothpick inserted in the center comes out clean.

Let the cakes cool in the pans for about 10 minutes before transferring them to a wire rack to cool completely.

To make the frosting, beat the remaining 1/2 cup softened butter until smooth. Gradually add the powdered sugar, alternating with 2 tbsp of milk and 1/2 tsp vanilla extract. Beat until light and fluffy, around 2-3 minutes.

Once the cakes are completely cool, spread frosting between the layers and over the top and sides of your cake.

Optionally, sprinkle some extra lavender on top for a stunning finishing touch.