Preheat your oven to 150°C (300°F) and line a 16cm (6-inch) baking pan with parchment paper. Wrap the pan in aluminum foil to prevent leaks.
Separate 3 large eggs into two bowls (about 60g each, shell included).
Whisk the yolks, then add 30ml vegetable oil, 200g Greek yogurt, and 15 ml honey. Stir until smooth.
Add 20g all-purpose flour and 18g cornstarch. Stir until the batter is smooth.
Add 1 tsp lemon juice and a pinch of salt, then beat until foamy. Gradually add 60g sugar in 3 batches until medium peaks form.
Gently fold in the egg whites in thirds, ensuring no white streaks remain. Be careful not to overmix.
Pour batter into the prepared pan, flatten the top, and tap gently to remove air bubbles. Place the pan in a water bath and bake for 50 minutes.
Let the cake cool in the pan for about 10 minutes, then remove from the pan and peel off parchment paper.
Slice the cake and enjoy its soft, fluffy texture with a tangy yogurt flavor and subtle honey sweetness.