This buckwheat olive oil cake features a super tender, fine and plush crumb thanks to a generous amount of olive oil. Buckwheat adds a nutty flavor that complements the rich chocolate ganache.
Preheat oven to 350 and grease and line a 9" cake pan with parchment. In the bowl of a stand mixer fitted with a whisk attachment, combine 3 large eggs and 1 cup + 2 tbsp granulated sugar. Mix on low to combine, then increase speed to medium and whip for 3 minutes until lightened and very foamy.
With the mixer on medium-low, steadily stream in 3/4 cup olive oil. Sprinkle 1 tsp baking powder and 3/4 tsp kosher salt over the top and combine. Add 3/4 cup buckwheat flour and mix to combine. Add 1 cup all-purpose flour and mix to just combine. Finally, stream in 3/4 cup milk and mix on medium-low until batter is smooth.
Pour batter into prepared pan and bake for 45-50 minutes, or until the edges are golden and the center springs back under your finger.
While the cake is baking, toast 3 tbsp milk powder, optional in a small skillet until golden, if using.
Heat 1/2 cup heavy cream until steaming (either ~1 minute in the microwave or on the stovetop). Place 4 oz dark chocolate, chopped in a large heat-proof bowl and add the toasted milk powder. Pour the heavy cream over and let stand for 1 minute, then whisk until melted. Place in the fridge and chill for at least 1 hour.
Using electric beaters, whip the ganache until light and fluffy and spread over the cooled cake. Top with a drizzle of extra virgin olive oil and flaky salt before serving.