Instructions:
- Preheat Oven: Preheat the oven to 350°F (180°C) and grease a 8-inch round cake pan.
- Prepare Dry Ingredients: In a bowl, whisk together the flour, baking powder, baking soda, and salt.
- Mix Wet Ingredients: In another bowl, mix the yogurt, sugar, vegetable oil, egg, and vanilla extract until well combined.
- Combine Ingredients: Gradually add the dry ingredients to the wet ingredients, stirring until just combined. Be careful not to overmix.
- Add Apples: Gently fold in the diced apple and ground cinnamon into the batter.
- Bake: Pour the batter into the prepared cake pan and spread it evenly. Bake for about 30-35 minutes, or until a toothpick inserted into the center comes out clean.
- Cool and Serve: Allow the cake to cool in the pan for 10 minutes, then transfer it to a wire rack to cool completely. Dust with powdered sugar before serving, if desired.
Note: This cake is best enjoyed fresh but can be stored in an airtight container at room temperature for up to 2 days.
