Ingredients
- 3 large eggs (160 g)
- 9 tablespoons (125 grams) unsalted butter, cold and cut into cubes
- ⅔ cup (130 grams) granulated sugar, divided
- 1 teaspoon vanilla extract
- 1 cup (125 grams) buckwheat flour
- 1 ¼ cup (125 grams) almond flour
- 1 tbsp (8 grams) baking powder
- 2 tablespoons olive oil
- 1 small apple (about 90 grams), peeled, cored and grated
- 1 tablespoon orange zest
- ½ teaspoon kosher salt
- ¼ teaspoon cream of tartar (or substitute ½ teaspoon lemon juice)
- 14 ounces (400 grams) lingonberry jam
- powdered sugar for dusting (optional)
Instructions
- Preheat oven to 350 F (180 C) and grease an 8 inch (20 cm) round cake tin.
- Separate the egg yolks and whites.
- Beat the cold cubed butter with an electric mixer until just softened (around 2 minutes). Add vanilla extract and half of the sugar (⅓ c or 65 g). Beat for five minutes, occasionally scraping the sides of the bowl.
- Add the yolks one at a time, beating the mixture for 30 second after each addition.
- Add the buckwheat flour, almond flour, and baking powder to the butter mixture and mix gently.
- Add the olive oil, grated apple and orange zest. Mix until fully incorporated.
- In a separate bowl combine the egg whites, salt and cream of tartar. Beat with clean whisks on medium speed until foamy.
- Increase the speed to high and gradually add the remaining sugar (⅓ c or 65 g). Continue beating until stiff peaks form (about 5 to 10 minutes).
- Add a few tablespoons of egg whites into the dough and mix well.* Carefully fold in the rest of the whipped egg whites.
- Pour the batter into the prepared tin and spread evenly. Bake for 40-45 minutes or until an inserted toothpick comes out clean.
- Let the cake cool for 10 minutes then turn out onto a wire rack to cool completely.
- Slice the cake in half horizontally. Spread a layer of jam on the bottom half of the cake and place the other half on top. Dust with powdered sugar if desired.
Notes
Folding egg whites into the batter: Mixing a few tablespoons of egg whites into the batter before folding in the rest will make the process easier.