Preheat oven or air fryer to 200°C / 390°F.
Line or lightly grease a small to medium baking pan.
Peel, core and chop the apples.
Place apples, eggs and Greek yogurt in a blender, adding sweetener if desired.
Blend until completely smooth and creamy.
Taste and adjust sweetness if needed.
Pour the mixture into the prepared pan and tap gently to level.
Bake in the oven for 45–50 minutes or in the air fryer for 30–35 minutes, until the edges are set and the centre is slightly tender.
Allow to cool in the pan, then slice and serve.