Preheat the oven to 350 degrees F.
In the large bowl of a stand mixer, cream together butter, oil, and sugar.
Add in eggs and vanilla and beat until light and fluffy, for a couple minutes.
Then add in the yogurt and mix until combined.
After you mill your flour, pour it through a sifter and sift until most of the bran is left behind.
In a separate mixing bowl for dry ingredients, mix together flour, baking powder, baking soda, and salt.
Working in batches, add ⅓ of the flour mixture into the batter, then half of the buttermilk, mixing well between each addition. Repeat, and end with adding in the last of the flour.
Pour cake batter into a baking sheet with raised edges and lined with parchment paper - you can use either a large baking sheet (about 13 x 18), or two smaller baking sheets.
Bake for 17-20 minutes.
Allow the cake to cool.
Using a 3 inch heart cookie cutter, cut out heart shapes while the cake is still in the pan.
Use a spatula to remove the hearts from the pan. If using a 3 inch cookie cutter, this will make approximately 20 hearts (10 heart cakes).
If the hearts are too thick, you can use a knife to cut a little bit off the backs of the hearts.
To make the icing, beat together butter, powdered sugar, milk, and vanilla until fluffy and smooth. Make sure the icing is not too stiff.
Put the icing in a ziploc bag or a piping bag and pipe the icing onto half of the hearts. Put the rest of the hearts on top of the iced hearts to make the cakes.
Place the heart cakes on a baking sheet and freeze for one hour.
Once the heart cakes have frozen, melt the white chocolate chips and coconut oil in 15-30 second increments in the microwave. Be careful not to burn the chocolate!
Take out ¼ cup of white chocolate and reserve for the drizzle.
Allow the white chocolate to cool down, then add in 3-4 drops of plant-based red food coloring.
Stir the white chocolate until the food coloring is mixed in.
To coat the cakes, take one heart cake and place it on a large fork. Holding over the bowl of chocolate, use a small measuring cup to dip into the chocolate and pour the chocolate over the heart cake while it is on the fork. Continue pouring the white chocolate over top of the cake until it is fully covered in chocolate.
Place the cakes on a baking sheet lined with wax paper or parchment paper.
There are two options for toppings. Option 1 must be done before the cakes have hardened.
Option 1: place the freeze dried strawberry powder and the powdered sugar in a small blender or food processor and blend together until pink. Using a sieve or sifter, sprinkle the powdered sugar on top of the hearts.
Option 2: once the cakes have hardened, take the reserved white chocolate and place in a ziploc bag. Snip a tiny corner off and drizzle the white chocolate in circular patterns overtop of the cakes and allow to harden.