01 - Preheat oven to 350°F. Grease and line three 8-inch round cake pans with parchment paper.
02 - Heat the milk until steaming without boiling. Add Earl Grey tea bags and steep for 15 minutes. Remove tea bags and allow milk to cool completely to room temperature.
03 - In a medium bowl, whisk together flour, baking powder, and salt until well combined.
04 - In a large bowl, beat softened butter and granulated sugar on medium-high speed until pale and fluffy, approximately 3 minutes. Add eggs one at a time, mixing thoroughly after each addition. Stir in vanilla extract and lemon zest.
05 - With mixer on low speed, add dry ingredients in three additions, alternating with cooled Earl Grey milk in two additions. Begin and end with flour mixture. Mix only until just combined to avoid overmixing.
06 - Divide batter evenly among prepared pans. Smooth tops with spatula. Bake for 28 to 32 minutes or until a wooden toothpick inserted in center comes out clean.
07 - Let cakes cool in pans for 10 minutes before carefully turning out onto wire racks to cool completely.
08 - In a small saucepan, bring water and granulated sugar to a simmer. Add Earl Grey tea bags and steep for 10 minutes. Discard tea bags and allow syrup to cool completely.
09 - Beat softened butter until creamy and smooth. Gradually add powdered sugar, alternating with whole milk, beating until light and fluffy. Mix in vanilla bean paste and pinch of salt until fully incorporated.
10 - Level cooled cake layers if necessary. Brush each layer generously with cooled London Fog syrup. Spread frosting between layers, then apply a thin crumb coat over the entire cake. Chill for 15 minutes, then finish with remaining frosting.
11 - Decorate with dried edible flowers and fresh lemon zest if desired. Refrigerate for 30 minutes before slicing for clean, professional cuts.