Preheat oven to 350°F.
Grease two round cake pans and line the bottom of each pan with a round of parchment paper. Set aside.
In a small mixing bowl sift together 2 cups flour, 1 tsp. baking soda, and 1 tsp. baking powder. Set aside.
In the bowl of a stand mixer, cream together, 1 stick softened butter with 1 cup sugar.
Once butter and sugar are fluffy, add remaining lemon zest and remaining lemon juice. Mix on high to incorporate.
Add the 3 eggs, one at a time, beating well after each one is added.
Reduce speed on mixer and add in half the dry ingredients along with half the sour cream.
Once well combined add the remaining dry ingredients and the remaining sour cream. Mix until well combined.
Divide the batter evenly between the two prepared caked pans.
Sprinkle the raspberries, blueberries and sliced strawberries evenly over the batter in both pans. Reserve some sliced strawberries to use as garnish.
Divide the crumb topping evenly between the two cake pans and gently press topping and berries down into the batter.
Bake cakes for 40-50 minutes or until a toothpick inserted in the middle comes out clean.
Remove cakes from oven and transfer pans onto a cooling rack. Cool cakes completely in the pans.