01 - Preheat oven to 350°F. Grease and flour two 8-inch round cake pans, lining bottoms with parchment paper.
02 - Whisk together flour, baking powder, baking soda, and salt in a medium bowl.
03 - Beat butter and sugar in a large bowl until light and fluffy, approximately 3–4 minutes.
04 - Add eggs one at a time, beating well after each addition. Mix in lemon zest and vanilla extract.
05 - Blend lemon juice, milk, and sour cream in a separate bowl or measuring cup.
06 - With mixer on low speed, alternately add flour mixture and lemon-milk mixture to butter mixture, beginning and ending with flour. Mix until just combined.
07 - Gently fold chopped strawberries into batter.
08 - Divide batter evenly between prepared pans and bake for 28–32 minutes until toothpick inserted in center comes out clean.
09 - Let cakes cool in pans for 10 minutes, then turn out onto wire racks to cool completely.
10 - Beat butter until creamy. Add powdered sugar, lemon zest, lemon juice, salt, and 2 tablespoons cream. Beat until fluffy, 3–5 minutes, adding more cream as needed for consistency.
11 - Level cake tops if needed. Spread buttercream between layers, then frost top and sides of cake.
12 - Garnish with fresh strawberries and lemon slices or zest curls.