• Preheat oven to 350 degrees F. Spray 2 (8 inch) cake pans with oil, line bottom with wax paper cut to fit. Spray wax paper and sides of pan with more oil and dust with flour. (This will definitely prevent the cake from sticking. It's the method I almost always use when baking a cake.)

For the cake

• In the bowl of a stand mixer fitted with paddle attachment sift together flour, sugar, baking powder,and salt.
• Add the butter, sour cream, eggs, vanilla, and strawberry puree to the dry ingredients and mix on medium speed until smooth, about 30 seconds. Scrape down sides to make sure all the flour is incorporated. Mix on medium speed for another minute.
• Divide batter evenly among cake pans and bake for 20-30 minutes on middle rack of oven.
• Let cool completely before filling and frosting.

For the whipped cream filling

• In a medium bowl combine heavy cream and cream of tatar and mix on high until soft peaks form. Add confectioner sugar and mix until stiff peaks are formed. Set aside.

For the Buttercream Frosting

• In the bowl of a stand mixer fitted with the paddle attachment cream the butter and shortening for 3-5 minutes. Add confectioner sugar and pour milk and vanilla over it. **Place a dish towel around mixer
• to prevent a cloud of sugar covering your kitchen. Turn mixer on low speed and mix for 1 minute then turn to high speed and mix for 3 minutes until smooth and creamy.

Put cake together

• Remove cooled cake from pans. Pipe around outer edge of bottom layer with buttercream frosting to create a dam so that your whipped cream filling and strawberries don't get squished out when you add your top layer. Add your whipped cream filling and layer with sliced strawberries. Place next cake layer on top and frost with buttercream.