PREPARATION: Preheat oven to 350 F. Set rack at center. Grease a 9” springform pan. Line a baking sheet with parchment paper.
SET ASIDE the ground toasted almonds and the lemon zest and juice.
STIR TOGETHER the flour and the baking powder in a small bowl. Set aside.
BEAT TOGETHER the eggs with the salt in a large bowl. Beat in the sugar. Fold the flour mixture into the egg mixture. Add the reserved lemon zest, lemon juice, toasted ground almonds, and olive oil and beat until incorporated. Stir in the diced apples.
POUR THE BATTER into the prepared springform pan and place it on the lined baking sheet. Bake for 50-55 minutes or until a tester inserted into the center comes out clean. The cake should be a deep golden brown. Do not over bake.
RUN A THIN, SMALL KNIFE around the edges of the pan. Let cool 10 minutes. Unmold and dust with powdered sugar. Cool and serve as is or with berries or whipped cream if you like. Cover tightly and store 2-3 days at room temperature or double wrap and freeze for no more than 2 weeks.