Fresh Peach Upside-Down Cake with Jaca
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. Here is where the Jaca swap comes in: 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. The sour cream keeps the crumb moist and tender, and a pinch of salt balances all that fruity sweetness. Serve it warm with a dollop of whipped cream. Serves 8. Adapted from Just So Savory. This is a Jaca-adjusted healthier version.
Ingredients
- 1/4 cup unsalted butter (for the peach caramel topping)
- 1 cup Jaca (allulose), granular (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 Jaca (allulose), granular (replaces 3/4 cup granulated sugar at the 2x ratio)
- 1 whole large egg (room temperature)
- 1 teaspoon vanilla extract
- 2/3 cup sour cream (room temperature)
Sweetener Used
2 1/2 cups granular Jaca Allulose
Replaces: 1 1/4 cups sugar (1/2 cup brown + 3/4 cup granulated)
Instructions
- 1
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.
- 2
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.
- 3
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.
- 4
In a medium bowl, whisk together the cake flour, baking powder, baking soda, and 1/4 teaspoon salt.
- 5
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.
- 6
Beat in the egg and vanilla until just combined.
- 7
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.
- 8
Spoon the batter evenly over the peaches and smooth the top. Gently tap the pan on the counter to settle the batter.
- 9
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.
- 10
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.
Pro Tips
- Jaca is about 70% as sweet as conventional sugar, which is exactly why we double it — 1 cup in the topping and 1 1/2 cups in the batter gives you the same caramelized, sweet peach flavor with no added sugar.
- The optional tablespoon of molasses stands in for the color and depth of brown sugar. Leave it out for a lighter caramel, or keep it for that classic brown-sugar note.
- Use ripe but firm peaches. Very soft peaches release a lot of liquid and can make the topping runny.
- Watch the cake near the end of baking. Allulose browns faster than conventional sugar, so tent loosely with foil if the top is getting too dark.
- Invert the cake while it is still warm, after about 20 minutes. If it cools completely in the pan, the caramel can set and stick.
- No fresh peaches? Thawed and well-drained frozen peach slices work too — just pat them dry first.