Preheat the oven to 350 degrees Fahrenheit. Generously grease one eight-inch round pan with nonstick spray.

Peel and core the apples. Cut the apples in half. With the cut side down, slice several 1/2-inch-wide wedges—enough to form a ring in the bottom of the pan. Cut the remaining apples into 1/4-inch cubes. Sprinkle one teaspoon of the lemon juice over the cubed apples and set them aside. Place the apple wedges in a concentric circle in the bottom of the prepared pan with the points facing upward (remember— it’s an upside-down cake). Sprinkle with the brown sugar, honey, and pomegranate concentrate.

In a small bowl, stir the flour, baking powder, baking soda, and salt just until combined. In a larger bowl, using an electric mixer on medium-high speed, combine the butter with the granulated sugar until fluffy. Add the eggs, vanilla, water, and lemon zest and beat to combine. Stir into the dry ingredients and beat for a minute until the batter is shiny and smooth. Add the apple cubes and fold gently with a spatula to combine. Pour or scoop the batter over the apple wedges. Rap the pan on the countertop to remove any air bubbles.

Bake the cake for 25 minutes and rotate the pan for even baking. Bake for 15 to 20 minutes more, until a toothpickcomes out clean and the cake is golden brown. Immediately run a knife around the edge of the cake and get your serving plate ready. Using pot holders (unless you have fingers of steel), place the cake plate over the pan and in one smooth motion flip it over. Wait until you hear the sound of the cake plop onto the plate and then tap the top of the inverted pan with a butter knife. Carefully lift the pan and if any apple bits are stuck in the pan, you can place them back on the cake while it is hot. This only works while it is hot. Let the cake cool completely before serving. Store, covered loosely, at room temperature.

Simmer the honey and pomegranate concentrate in a small saucepan over medium-low heat for a few minutes, until beginning to boil.

Remove the saucepan from the heat, carefully add the rum, and give it a minute to thicken. Pour over the cake and serve, or slice the cake and pour over each serving.