Preheat oven to 350 degrees F. Grease and prep round cake pans with parchment paper and set aside.
Using your electric stand mixer fitted with the paddle attachment, beat the butter on medium to high speed for about 30 seconds. Gradually pour in the sugar, about 1/4 cup at a time, mixing until well combined. Scrape sides of bowl as needed and mix for about 2 more minutes. Add the eggs, one at a time, beating well after each addition. Add in the lemonade concentrate, vanilla, sour cream and strawberry jam and mix until combined.
Using a separate medium-sized mixing bowl, mix together the flour, baking powder, baking soda, and salt. Pour the flour mixture into the wet ingredients slowly, while your mixer is on low to medium speed until combined. Pour the cake batter evenly into the prepared cake pans and bake for 30 to 35 minutes or until the top springs back when lightly touched. Cool in pans on a wire rack.