Prep the pan and air fryer. Lightly grease a 7-inch round cake pan (or similar size that fits your air fryer basket). Line the bottom with parchment for easy release.
Preheat the air fryer to 320°F (160°C) for 3–5 minutes.
Mix the wet ingredients. In a medium bowl, whisk yogurt, eggs, sugar, oil, vanilla, and lemon zest until smooth and glossy, about 30–45 seconds.
Combine dry ingredients. In a separate bowl, whisk together flour, baking powder, baking soda, and salt to evenly distribute the leavening.
Bring it together. Add the dry ingredients to the wet and whisk gently until just combined. Stop as soon as you no longer see dry flour. Do not overmix.
Fill the pan. Pour the batter into the prepared pan and smooth the top with a spatula. Tap the pan on the counter 2–3 times to release large air bubbles.
Air fry. Place the pan in the air fryer basket.
Cook at 320°F (160°C) for 28–35 minutes, depending on your model and pan depth. Start checking at 25 minutes. The cake is done when a toothpick comes out clean or with a few moist crumbs.
Cool. Let the cake cool in the pan for 10 minutes.
Run a knife around the edge, then turn it out onto a rack. Peel off the parchment and let it cool completely, 30–45 minutes.
Finish and serve. Dust with powdered sugar or add a thin glaze. Slice and enjoy with berries, yogurt, or a spoonful of jam.