As a pastry chef, I have been asked to make chiffon cake a lot, especially by Japanese customers. The kabocha flavor is easily one of the most popular chiffon cake requests I receive. Many miss the airy texture of a classic Japanese chiffon paired with authentic kabocha flavor—which is distinctly different from American pumpkin desserts that are typically loaded with heavy spices like cinnamon and nutmeg. Real kabocha brings a naturally sweet, rich, chestnut-like depth that shines cleanly when folded into a feather-light crumb and paired with a silky Kabocha Diplomat Cream.
Why You’ll Love This Cake
- Pure, Clean Kabocha Flavor (No Heavy Spices): Unlike traditional Western pumpkin treats, this recipe lets the natural, sweet squash flavor take center stage without being overwhelmed by spices. However, if you love warm autumn notes, feel free to add a dash of cinnamon, nutmeg, or pumpkin pie spice to the batter!
- Naturally Wholesome: Kabocha squash is naturally rich in dietary fiber, beta-carotene, and vitamins, adding natural sweetness, moisture, and density-free body to the cake batter.
- Prep-Ahead Friendly: You can easily prepare your squash paste ahead of time using my step-by-step guide on how to cut and store kabocha squash.
- Freezer-Friendly Delight: Both the baked chiffon cake and the assembled cake with Kabocha Diplomat Cream freeze remarkably well! Slice individual portions, wrap them tightly in plastic wrap, and freeze for up to a month. Thaw in the refrigerator for a quick, bakery-style slice whenever cravings strike.
Ingredients
Yield: One 17cm aluminum chiffon cake pan + cream topping/filling
Kabocha Chiffon Cake
- 70g Egg Yolks (~4 large egg yolks), room temperature
- 20g Granulated Sugar (for yolks)
- 15g Taihaku White Sesame Oil (or neutral baking oil)
- 50g Whole Milk, room temperature
- 60g Kabocha Paste (steamed, mashed, and passed through a fine strainer — see how to cut and store kabocha squash for prep tips)
- 65g Japanese Pastry Flour (Violet or cake flour), sifted
- 2 g baking powder
- 110g Egg Whites (~3 to 4 large egg whites), well-chilled
- 65 g granulated sugar (for meringue)
Signature Kabocha Diplomat Cream
Base 1: Kabocha An (makes ~340g total)
- 300g Kabocha Paste (steamed, mashed, and passed through a mesh strainer)
- 40g Granulated Sugar
Base 2: Heavy Cream (10% sugar)
- 25.5g Heavy Cream (chilled)
- 2.5g Granulated Sugar (yields 28g whipped cream)
Final Cream Assembly Ratio
- 140g Kabocha An (cooled)
- 70g Pastry Cream (50% relative to Kabocha An)
- 28g Sweetened Whipped Cream (20% relative to Kabocha An)
Instructions
1. Prepare the Kabocha Chiffon Cake
- Prep: Preheat oven to 165°C (330°F). Keep your 17cm aluminum chiffon cake pan ungreased and dry.
- Yolk Base: In a large bowl, whisk egg yolks and 20g sugar until pale. Whisk in white sesame oil, whole milk, and 60g smooth kabocha paste until emulsified.
- Dry Ingredients: Sift pastry flour and baking powder into the yolk mixture. Whisk gently until smooth and lump-free.
- Meringue: In a clean, oil-free bowl, whip cold egg whites until foamy. Gradually add 65g sugar in three additions, beating until glossy, firm peaks form with a slight hook at the tip.
- Fold: Fold one-third of the meringue into the kabocha yolk batter to lighten. Switch to a silicone spatula, add half of the remaining meringue, and fold gently. Add the final portion and fold just until uniform.
- Bake: Pour batter into the ungreased pan. Run a bamboo skewer through the batter in a spiral pattern to pop trapped air pockets. Bake at 165°C (330°F) for 35 to 40 minutes.
- Cool: Immediately invert the pan over a bottle or rack. Cool completely upside down (2 to 3 hours) before unmolding with a chiffon knife.
2. Make the Kabocha An Base
- In a microwave-safe bowl, combine 300g kabocha paste and 40g sugar.
- Microwave in short 45-to-60-second bursts, stirring thoroughly with a spatula between intervals to evaporate excess moisture.
- Stop when the paste reaches a smooth, non-sticky anko consistency (holds its shape on a spatula). Allow to cool completely before using.
3. Assemble the Kabocha Diplomat Cream
- Whip 25.5g heavy cream with 2.5g sugar until soft-to-medium peaks form (yielding 28g whipped cream).
- Smooth 70g chilled pastry cream with a spatula.
- Whisk 140g cooled Kabocha An into the pastry cream until smooth and fully blended.
- Gently fold in the 28g whipped cream until uniform and silky.
- Pipe onto slice portions or fill the chiffon center hole using a piping bag.
Frequently Asked Questions
Can I use canned pumpkin puree instead of homemade kabocha paste?
Yes, but you will need to adjust your liquids and sugar. Canned Western pumpkin puree contains significantly more water and has a higher natural acidity and lower sugar content than Japanese kabocha squash.
If using canned pumpkin puree:
*Reduce the milk slightly: Reduce the milk in the chiffon batter from 50g to 40g–45g to account for the extra moisture in the canned puree.
*Adjust the sugar: Canned pumpkin is less naturally sweet than kabocha. You may want to add an extra 5g of sugar to the yolk batter.
*Cook down the puree longer: For the Kabocha An base, canned pumpkin will require extra microwave or stovetop cooking time to evaporate enough water to reach a hold-its-shape anko texture.
Why do I need an ungreased aluminum pan for chiffon cake?
Chiffon batter relies on climbing the bare sides and center tube of the pan as it expands in the oven. If the pan is greased or non-stick, the delicate egg white structure will slide down and collapse instead of clinging to the walls, resulting in a dense, sunken cake.
Can I make the Kabocha Diplomat Cream ahead of time?
Yes! You can prepare the Kabocha An up to 3 days in advance and store it covered in the refrigerator. Once fully assembled with the pastry cream and whipped cream, the diplomat cream keeps well in an airtight container or piping bag in the fridge for up to 48 hours.
Kabocha Pumpkin Chiffon Cake with Kabocha Diplomat Cream
Equipment
- 1 17cm (6-inch base / 7-inch top) chiffon cake mold
Ingredients
Kabocha Chiffon Cake
- 70 g egg yolks approx. 4 large yolks, room temperature
- 20 g granulated sugar for yolk batter
- 15 g Taihaku white sesame oil or neutral baking oil
- 50 g whole milk room temperature
- 60 g kabocha squash paste steamed, mashed, and finely strained
- 65 g Japanese pastry flour Violet brand or cake flour, sifted
- 2 g baking powder
- 110 g egg whites approx. 3–4 large whites, well-chilled
- 65 g granulated sugar for meringue
Kabocha An Base
- 300 g kabocha squash paste steamed, mashed, and finely strained
- 40 g granulated sugar
Kabocha Diplomat Cream Assembly
- 140 g Kabocha An cooled, from base above
- 70 g pastry cream chilled
- 25.5 g heavy cream chilled
- 2.5 g granulated sugar for whipped cream
Instructions
Kabocha Chiffon Cake
- Preheat your oven to 165°C (330°F). Prepare a 17cm aluminum chiffon cake pan, keeping it completely ungreased and dry.
- Sift in Japanese pastry flour and baking powder; whisk gently until smooth and free of lumps. (Optional: add 1/4 tsp ground cinnamon or pumpkin pie spice here if desired).
- In a separate oil-free bowl, beat cold egg whites until foamy. Add 65g sugar in three gradual additions, whipping until glossy, firm peaks form with a slight hook at the tip.
- Fold 1/3 of the meringue into the yolk mixture to loosen. Fold in the remaining meringue in two additions using a silicone spatula until just uniform.
- Pour batter into the ungreased pan from a slight height. Run a bamboo skewer in a spiral pattern to pop trapped air pockets.
- Bake at 165°C (330°F) for 35 to 40 minutes until the cake rises fully and springs back when pressed.
- Immediately invert the pan upside down over a bottle or rack. Allow to cool completely upside down for 2 to 3 hours before unmolding.
Kabocha An Base
- Prepare raw kabocha squash (steam deseeded chunks until tender and press flesh through a fine mesh sieve).
- Combine 300g strained kabocha paste and 40g sugar in a microwave-safe bowl.
- Microwave in 45-to-60-second bursts, stirring with a spatula between intervals to evaporate moisture until an anko-like texture is reached. Cool completely.
Kabocha Diplomat Cream
- Whip 25.5g heavy cream with 2.5g sugar to soft-to-medium peaks (yielding 28g whipped cream).
- Smooth 70g chilled pastry cream with a spatula, then whisk in 140g cooled Kabocha An until smooth.
- Gently fold in the 28g whipped cream until silky. Pipe onto cake.
Notes
- Kabocha Prep Guide: For step-by-step instructions on breaking down and storing fresh squash, see our tutorial on how to cut and store kabocha squash.
- Pan Requirement: Always use an ungreased aluminum chiffon pan. Greasing or using a non-stick pan will cause the batter to slide down and collapse instead of clinging to the sides as it rises.
- Inverting is Mandatory: Chiffon cakes must cool completely upside down immediately after baking to preserve their tall, feather-light structure without collapsing under gravity.
- Freezing Instructions: Wrap individual uncreamed cake slices or assembled creamed slices tightly in plastic wrap and freeze for up to 1 month. Thaw in the refrigerator before serving.
