01 - Set oven to 350°F (180°C) and allow to fully preheat.
02 - Grease an 8-inch cake pan thoroughly. Arrange the drained pineapple rings evenly across the base.
03 - Combine whole wheat flour, coconut sugar, and baking powder in a mixing bowl.
04 - Add unsweetened applesauce, water or plant-based milk, and vanilla extract to the dry mixture. Stir until the batter achieves a consistent smooth texture.
05 - Pour batter gently over the arranged pineapple rings, spreading evenly.
06 - Transfer pan to oven and bake for 30 minutes, or until a toothpick inserted into the center emerges clean.
07 - Allow baked cake to cool for 10 minutes in the pan. Carefully invert onto a serving plate and lift off pan.