Strawberry Cake 

1. In a blender or food processor, blend the strawberries into a smooth puree. You should end up with a heaping 1 cup of strawberry puree.
2. Pour strawberry puree into a medium deep-bottom saucepan and cook puree under medium low heat until it is reduced by half and takes on a thick, paste-like consistency (similar to the consistency of tomato paste as a point of reference). You should end up with a 1/2 cup of reduced strawberry puree.
3. Allow strawberry puree reduction to cool completely before using in cake batter.
4. Preheat the oven to 325F (165C). Grease and line (3) 6 inch round pans with parchment paper cutout. Alternatively, strawberry cake may be made as a two layer 8 or 9 inch cake.
5. In a medium mixing bowl, add the flour, baking powder, baking soda, and salt. Whisk ingredients together to combine.
6. Add the milk and vinegar into a small mixing bowl or measuring cup and whisk to combine. Set aside to allow mixture to thicken up before using.
7. In the bowl of a stand mixer fitted with paddle attachment or in a large mixing bowl with a hand-held mixer, add and cream the butter, oil and sugar together at medium high speed until mixture appears thick and fluffy in appearance, about 2-3 minutes.
8. Mix the reduced strawberry puree and vanilla extract into creamed butter mixture to combine, about 1 minute.
9. Next, beat the eggs into wet batter one at a time ensuring that the previous egg is completely incorporated before adding and beating in the next egg.
10. Reduce mixer speed to low. In an alternating fashion, starting and ending with the dry ingredients, mix half of the dry ingredients into wet batter, followed by the milk and vinegar mixture, and ending with the remaining dry ingredients.
11. Stop the mixer and use a flexible (silicone) spatula to scrape the sides and base of the bowl.
12. Resume mixing cake batter at medium speed for additional 30-60 seconds to help ensure an evenly smooth batter.
13. Divide cake batter into prepared baking pans and bake for 30-35 minutes, rotating the pans halfway through bake time. Cakes are ready once a toothpick inserted into the center of cakes comes out clean.
14. Allow the cakes to cool in baking pans for 5-10 minutes before transferring to a cooling rack to cool completely to room temperature. 

Strawberry Buttercream Frosting 

1. Place freeze-dried strawberries in coffee grinder/food processor and grind into a fine powder.
2. In a stand mixer fitted with paddle attachment or in a large mixing bowl with a hand-held electric mixer, cream the butter at medium high speed until mixture is smooth and fluffy in appearance, about 2-3 minutes.
3. Reduce mixer speed to low and mix in 2 cups of the confectioners’ sugar and powdered freeze-dried strawberries into creamed butter. Gradually increase mixer speed back to medium.
4. Once all the sugar and powdered strawberries have been incorporated into butter, mix in the heavy whipping cream and vanilla extract (optional) into buttercream.
5. If buttercream appears to be on the soft side, mix in the remaining 1/2 cup of confectioners’ sugar 1/4 cup at a time (may not need to use all of the remaining sugar) until a thick but spreadable consistency is reached.
6. If buttercream appears too thick, mix in additional cream 1/2 teaspoon at a time until the desired consistency (thick but spreadable) is reached.
7. Increase mixer speed to medium high and mix strawberry buttercream for an additional 30-60 seconds. The resulting buttercream should be smooth and fluffy in appearance.

Assembly

1. Remove the domed tops off cooled cakes with a serrated knife or cake leveler. This will allow cakes to be evenly stacked.
2. Place a clean surface on top of a cake turntable i.e. cake stand/cake board and spread a small amount of the strawberry buttercream onto the center.
3. Position the first cake layer faced up in the center of the prepared surface.
4. Spoon 1/2 cup of the buttercream onto cake and spread into an even layer using an offset spatula.
5. Repeat layering process once more with the second cake layer and buttercream.
6. Place the final cake layer faced down on top of the second layer.
7. Using an offset spatula, fill in the gaps between the cake layers and spread a thin layer of the buttercream along the sides of the cake.
8. Smooth out buttercream with a bench scraper.
9. Apply more buttercream over any obvious gaps in the cake and repeat smoothing with a bench scraper process as necessary. To preserve semi-naked cake look, take care not to add too much buttercream to cake.
10. Add a small amount of the buttercream on the top layer of cake – just enough to spread into a thin layer with a offset spatula (about 2-3 tablespoons of buttercream).
11. Transfer remaining buttercream to a pastry bag fitted with desired piping tip. I used a Wilton 6B piping tip.
12. Sprinkle powdered freeze-dried strawberries along the top border of cake (optional).
13. Pipe a dollop of the strawberry buttercream on the top of frosted cake along the outer perimeter. Leave about a 1/4 inch gap between each piped dollop.
14. Fill the gaps between piped buttercream with a halved fresh strawberry. Try to use small strawberries as opposed to large strawberries if possible. This will help make the strawberries look proportional to the piped buttercream.
15. Serve right away or refrigerate until ready to serve.