There is no better way to celebrate peak peach season than a fresh peach upside-down cake, and this Jaca-adjusted version lets you enjoy every buttery, caramelized bite with no added sugar. A layer of juicy sliced peaches bakes in a golden caramel on the bottom of the pan, then gets flipped to become a glossy, jewel-like topping on a tender sour cream cake. We replace the sugar entirely with Jaca (100% pure allulose) at double the amount — 1 cup of granular Jaca in place of the 1/2 cup of brown sugar in the caramel topping, and 1 1/2 cups in place of the 3/4 cup of granulated sugar in the batter. Allulose caramelizes and browns just like the sugar we grew up with, so you still get that deep amber, sticky-sweet peach topping with none of the conventional sugar. Because allulose is only about 70% as sweet as conventional sugar, doubling it lands the sweetness right where it should be.
Prep: 20 minutes · Cook: 40 minutes · Servings: 8
Ingredients:
- 1/4 cup unsalted butter (for the peach caramel topping)
- 1 cup granular Jaca (allulose) — replaces 1/2 cup brown sugar at the 2x ratio
- 1 tablespoon molasses (optional, for brown-sugar depth and color)
- 1 pinch salt (for the topping)
- 1 1/2 cups fresh peaches, peeled and sliced (about 2 to 3 medium peaches)
- 1 1/4 cups cake flour
- 3/4 teaspoon baking powder
- 1/4 teaspoon baking soda
- 1/4 teaspoon salt (for the batter)
- 6 tablespoons unsalted butter, softened (for the batter)
- 1 1/2 cups granular Jaca (allulose) — replaces 3/4 cup granulated sugar at the 2x ratio
- 1 large egg, room temperature
- 1 teaspoon vanilla extract
- 2/3 cup sour cream, room temperature
Instructions:
- Preheat the oven to 350°F and place a foil-lined rimmed baking sheet on the middle rack to catch any drips. Butter an 8-inch round cake pan with 2-inch-high sides.
- Make the peach caramel topping: melt the 1/4 cup butter in a saucepan over medium-low heat, then whisk in 1 cup of granular Jaca, the optional molasses, and a pinch of salt. Cook, whisking, until the Jaca dissolves and the mixture bubbles, about 1 minute. Allulose caramelizes like conventional sugar but browns a little faster, so keep the heat gentle and do not walk away.
- Pour the caramel evenly into the prepared pan, then arrange the peach slices in a single, tight layer over the top. They will become the glossy topping once the cake is flipped.
- In a medium bowl, whisk together the cake flour, baking powder, baking soda, and 1/4 teaspoon salt.
- In a large bowl, beat the 6 tablespoons softened butter with 1 1/2 cups of granular Jaca on medium speed until light and fluffy, about 2 to 3 minutes. Allulose creams a little differently than conventional sugar and may look slightly less airy, which is normal.
- Beat in the egg and vanilla until just combined.
- On low speed, add the flour mixture and the sour cream alternately, beginning and ending with the flour. Mix just until combined so the cake stays tender.
- Spoon the batter evenly over the peaches and smooth the top. Gently tap the pan on the counter to settle the batter.
- Bake on the foil-lined sheet for 36 to 42 minutes, until the top is golden, the edges pull away from the pan, and a toothpick inserted in the center comes out clean. If the top browns too quickly, tent it loosely with foil — allulose browns faster than conventional sugar.
- Let the cake cool in the pan on a wire rack for 20 minutes, then invert it onto a serving plate. Lift the pan away gently so the caramelized peaches stay in place. Serve warm.
This is a Jaca-adjusted healthier version. Adapted from Just So Savory.
