Diabetic-Friendly Pineapple Upside Down Cake

My father-in-law requested that I make his favorite Pineapple Upside Down cake this morning which is one of my favorite cakes as well (any fruit variety of this cake for that matter). But since he's diabetic, he asked that I lessen the sugar a little bit so he could somewhat indulge on this guilt-free. I don't think lessening the amount of sugar in a cake makes it safe for a diabetic to consume and given the caramel required to make the topping and my not wanting to play around with the sugar proportions of the recipe, I decided to use coconut sugar instead, replacing all the sugar (1:1) required for the cake. I've actually thought of making some form of dessert using coco sugar for my FIL during the Holiday season but haven't gotten around to making some because I really didn't know which recipes to play around with. The safest would probably be bars and cookies but he doesn't like them. So now that he actually requested for a cake, I might as well try it on this one.

Coco sugar, which is made from the sap of coconut trees, looks a lot like dark muscovado sugar and to me, they even taste the same. According to the manufacturers, coco sugar can perform really well as a direct sugar substitute to any baked product, not affecting taste and how the batter rises, etc. I was curious to see how this would melt and caramelize though but to my surprise, it melts just like muscovado sugar, even faster. But unlike its cousin, the color of coco sugar when exposed to high heat like in caramelizing, becomes a lot darker, almost burnt-looking. It also took a little while for it to get incorporated into the melted butter but I was still able to achieve the perfect consistency for the caramel topping.

For the cake, I used Rose Levy Beranbaum's recipe for Apple Upside Down cake -- replacing the apples with pineapples, cherries and pecans and of course, replacing the 3/4 cup sugar with 3/4 cup coco sugar. I did nothing differently in the procedure and the cake baked at the time stated in the recipe, which was just a little over 35 minutes. The batter rose beautifully to my surprise and it also inverted perfectly without any fruit or cake sticking to the pan. And the smell is just wonderful! Just like how a pineapple upside down cake should smell like. No one would think that I used a different kind of sugar on this one! My only complaint about this sugar though is that, like what I mentioned previously, it gets so dark (almost black but not bitter) which makes the cake look charred and somewhat unattractive LOL.

Fast forward to cooling time and I got permission from my FIL to slice a piece for myself just so I know that I'm not giving him anything that tastes horrible. :P I was also curious to see how the crumb looks like. As you can see below, the cake is a lot darker because of the coco sugar and the crumb a little denser.

ETA: Since I've been getting a lot of hits on this post lately I thought I'd share the recipe for this Pineapple Upside-Down Cake to you.  For more Diabetic-Friendly desserts do check out another post where I made Chinese Almond Cookies made out of coco sugar.  The results were great!

Pineapple Upside-Down Cake
(Adapted from Rose Levy Beranbaum's Apple Upside-Down Cake recipe from her book Rose's Heavenly Cakes)

Equipment: One 9 x 2-inch round pan, encircled with cake strip and the bottom coated with shortening and topped with a parchment round

Pineapple and Pecan Topping

10-12 pieces fresh or canned (unsweetened) pineapple rings, enough to decoratively cover the bottom and sides of the pan
1 teaspoon lemon juice, freshly squeezed
1/3 cup firmly packed coconut sugar
4 tablespoons/57 grams unsalted butter
2/3 cup/66 grams pecan halves, lightly toasted
Maraschino or bing cherries for garnish

Batter

3 1/2 tablespoons/56 grams large egg yolks, at room temperature
1/2 cup/121 grams sour cream
1 1/4 teaspoons pure vanilla extract
1 1/2 cups/150 grams sifted cake flour (or exact weight of bleached all-purpose flour)
3/4 cup/150 grams coconut sugar
3/4 teaspoon baking powder
1/4 teaspoon baking soda
1/4 teaspoon salt
9 tablespoons/128 grams unsalted butter

Procedure:

Twenty minutes or more before baking, set the oven rack in the lower third of the oven and preheat the oven to 350 F.

Make the pineapple topping: in a small heavy saucepan, preferably non-stick, melt the butter.  Use 1 tablespoon to coat the parchment-lined bottom and the sides of the cake pan.  Add the coco sugar and the lemon juice to the butter remaining in the saucepan.  Bring to a boil, adding a few tablespoons of water or unsweetened pineapple juice if necessary, stirring constantly the first minute then leave to boil for about 3 or so minutes until it is bubbling thickly and dark amber in color.  This step is important to ensure a nice caramel color to the topping.

Pour the mixture into the prepared cake pan, tilting to coat the entire bottom.  Don't worry if the mixture doesn't completely cover the pan, it will melt and spread during baking.  Arrange the pineapple rings, pecan halves, and cherries attractively on the bottom of the pan.  Slice a few rings in half and arrange them standing up around the inner sides of the pan.  This step is important as the batter will rise higher and will prevent sticking while unmolding the cake.  Set the pan aside.

Prepare the batter: In a medium bowl, whisk the yolks, 2 tablespoons of the sour cream, and the vanilla until combined.  In the bowl of a stand mixer fitted with a flat beater, mix the flour, coco sugar, baking powder, baking soda, and salt on low speed for 30 seconds.  Add the butter and the remaining sour cream.  Mix on low speed until the dry ingredients are moistened.  Raise the speed to medium and beat or 1 1/2 minutes.  Scrape down the sides of the bowl.

Starting on medium-low speed, gradually add the egg mixture to the batter in two parts, beating on medium speed for 30 seconds after each addition to incorporate the ingredients and strengthen the structure.  Scrape down the sides of the bowl.  Using a silicone spatula, drop the batter in big blobs on top of the pineapples then smooth the surface evenly with a small offset spatula while keeping the apples in an attractive pattern.

Bake the cake: Place the pan in the oven and bake for 35 to 45 minutes or until golden brown, a wire cake tester inserted in the center comes out clean, and the cake springs back when pressed lightly in the center.

Unmold the cake immediately by running a small metal spatula between the sides of the pan and the cake, pressing firmly against the pan, and invert the cake at once onto a serving plate.  Leave the pan in place for 1 to 2 minutes before lifting it off.  If any apple slices have stuck to the pan, use a small metal spatula to place them back on the cake.  Scatter the toasted walnuts on top.  Serve warm or room temperature.

VERDICT: Yummy! I sliced myself a small piece thinking it was enough but went back and got a bigger slice! The sweetness level of the coco sugar is exactly like the sugars derived from cane juice so for anyone looking into using this in lieu of cane sugar, I'd use a 1:1 ratio. The cake itself is also so moist and melts in your mouth! I think I'm going to try making more desserts out of coco sugar since this one was such a success. My father-in-law will definitely be happy that he can finally enjoy his favorite cake without the guilt. :)

UPDATE: I baked a this exact cake for a diabetic friend and he told me that his blood sugar didn't shoot up at all.  So definitely coco sugar works really well as a sugar substitute for diabetic people.