Cakes and Cupcakes

Rhubarb and Custard Cake

This simple Rhubarb and Custard Cake is easy to make and perfect for sharing. A fluffy vanilla sponge with rhubarb

  • Serves 16
  • Prep 15 minutes
  • Cook 1 hour
  • Total 1 hour
Jump to the recipe
Rhubarb and Custard Cake

You will also love my Rhubarb Crumble with Oat Crumble Topping 🙂

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Rhubarb and custard are such a classic flavour combo! I absolutely love the tanginess of rhubarb contrasted with the creamy sweetness of custard.

This easy rhubarb custard cake takes minutes to prepare and will disappear just as quickly, mark my words. Simply dusted with icing sugar it makes for perfect breakfast snacking cake.

Add some warm custard or vanilla ice cream and your rhubarb cake is ready for the ball 🙂

rhubarb custard cake traybake, sliced overhead shot

Rhubarb Custard Cake Ingredients

Let’s take a look at what ingredients we will need to make this cake.

  • Rhubarb: forced rhubarb will provide a prettier colour but regular rhubarb is just as delicious if a bit less showy! You can also use a mix of rhubarb and strawberries if you like.
  • Strawberry jelly powder: I mixed my diced rhubarb with strawberry jelly crystals just to add a hint of strawberry sweetness. This is optional though – feel free to skip entirely.
  • Both plain flour (all purpose flour) with added baking powder or self raising flour on its own can be used.
  • Sugar: I used caster sugar (superfine sugar)
  • Large eggs
  • Softened butter or baking spread such as Stork
  • Vanilla bean paste or vanilla extract
  • Custard powder, sugar, milk and butter (see recipe notes)
  • Flaked almonds, to top

How to Make This Rhubarb and Custard Cake

↓ For the full ingredients and detailed method, jump to the recipe card.

Preheat the oven to 170°C (340°F). Line a  9×13 inch with baking paper or a reusable liner. Dice the rhubarb into small pieces, without peeling it. Rinse well, pat dry and sprinkle with the strawberry jelly crystals, if using.

Measure the flour, sugar and baking powder into a mixing bowl and stir to combine. Add the vanilla bean paste, eggs and baking spread and beat together with a hand or stand mixer until the batter is smooth. Use a spatula to scrape the sides and bottom of your bowl halfway through to make sure all the ingredients are well mixed.

beating rhubarb cake batter with an electric hand mixer

PREPARE THE CUSTARD

Add the custard powder, sugar and milk into a saucepan and stir to combine. Cook over low heat for about five minutes, stirring, until the custard thickens.

Take off the heat and stir in the vanilla and butter. Press some clingfilm on top of the custard to prevent a skin forming unless you are using right away.

custard in a saucepan

LAYER CAKE INGREDIENTS INTO CAKE PAN

Spoon about three quarters of the batter into your prepared cake pan. Add the diced rhubarb over the batter, spreading it out. Do not press the rhubarb into the batter, just scatter it over the top.

Dollop the custard over the rhubarb, spacing it out so there’s gaps. Add the remaining batter to fill in these gaps, without spreading it too much. Scatter the flaked almonds on top.

rhubarb and custard cake ingredients layered in a lined cake pan

Bake for an hour (or up to 75 minutes) or until the cake is risen, golden and springy to the touch. Allow the cake to cool in the cake pan for ten minutes before lifting it out of the pan and cooling on a wire rack. Dust with icing sugar, slice and enjoy!

Rhubarb and custard cake traybake sliced on a pink background

Recipe Notes

  • You do not need to peel or precook the rhubarb for this cake recipe. If the rhubarb stalk is really thick you can slice it in half lengthwise before dicing.
  • The rhubarb will sink into the batter as the cake bakes. For this reason avoid pressing the rhubarb into the batter, simply place it on top of it.
  • Instant custard powder (Bird’s Traditional Custard Powder) is a very common ingredient in the UK. Custard powder is essentially cornstarch, colouring and vanilla flavouring to which you add sugar, milk and butter. In the US you can substitute with instant Vanilla Pudding, leaving out the sugar as it is already included.
  • Storage: This cake is best served on the day it is baked. It will keep for a couple of days in a covered container away from direct heat. You can also store it in the fridge, wrapped in foil.
  • Can you freeze rhubarb and custard cake? You can freeze the cake whole or in slices for up to three months, well wrapped. Thaw overnight in the fridge before serving.
close up on slices of rhubarb custard cake, some on their side to show the interior texture

HAVE YOU MADE MY RHUBARB CUSTARD CAKE RECIPE? Please leave a rating, post a photo on my Facebook page, share it on Instagram, or save it to Pinterest with the tag #Nusde and make my day 🙂

Recipe

Rhubarb and Custard Cake

This simple Rhubarb and Custard Cake is easy to make and perfect for sharing. A fluffy vanilla sponge with rhubarb and custard baked right into the batter. Delicious as a teatime treat or served with ice cream for dessert!

  • Serves 16
  • Prep 15 minutes
  • Cook 1 hour
  • Total 1 hour

Ingredients

For the rhubarb

  • 1 ½ cups (300g) diced rhubarb (forced rhubarb preferably)
  • 2 tbsp strawberry jelly powder ((optional))

For the cake

  • 2 cups (250g) all-purpose flour ((= plain flour), * see note 1)
  • 2 tsp baking powder
  • 1 ¼ cups (250g) sugar, superfine sugar ((= caster sugar))
  • 4 large eggs
  • 1 cup (225g) softened butter (or baking spread such as Stork)
  • 2 tsp vanilla bean paste (or vanilla extract)

For the custard

  • 2 tbsp custard powder (* see note 2)
  • 2 tbsp sugar
  • 1 cup (240ml) milk
  • 2 tbsp butter (, cubed)
  • 2 tsp vanilla bean paste

To top

  • 2 tbsp flaked almonds
  • powdered sugar ((= icing sugar))

Method

  1. 1

    Preheat the oven to 340°F (170°C). Line a 9×13 inch with baking paper or a reusable liner.

  2. 2

    Dice the rhubarb into small pieces, without peeling it. Rinse well, pat dry and sprinkle with the strawberry jelly crystals, if using.

  3. 3

    Measure the flour, sugar and baking powder into a mixing bowl and stir to combine.

  4. 4

    Add the vanilla bean paste, eggs and baking spread and beat together with a hand or stand mixer until the batter is smooth. Use a spatula to scrape the sides and bottom of your bowl halfway through to make sure all the ingredients are well mixed.

  5. 5

    Prepare the custard: add the custard powder, sugar and milk into a saucepan and stir to combine. Cook over low heat for about five minutes, stirring, until the custard thickens.

  6. 6

    Take off the heat and stir in the vanilla and butter. Press some clingfilm on top of the custard to prevent a skin forming unless you are using right away.

  7. 7

    Spoon about three quarters of the batter into your prepared cake pan.

  8. 8

    Add the diced rhubarb over the batter, spreading it out. Do not press the rhubarb into the batter, just scatter it over the top.

  9. 9

    Dollop the custard over the rhubarb, spacing it out so there’s gaps. Add the remaining batter to fill in these gaps, without spreading it too much. Scatter the flaked almonds on top.

  10. 10

    Bake for an hour to 75 minutes, until the cake is risen, golden and springy to the touch. Allow the cake to cool in the cake pan for ten minutes before lifting it out of the pan and cooling on a wire rack.

  11. 11

    Dust with icing sugar, slice and enjoy!

Notes

NOTE 1: If you are using self raising flour then leave out the baking powder. NOTE 2: If you can’t find custard powder you can sub with instant vanilla pudding, leaving out the sugar as it is already included. GENERAL NOTES You do not need to peel or precook the rhubarb for this cake recipe. If the rhubarb stalk is really thick you can slice it in half lengthwise before dicing. Rhubarb will sink into the batter as the cake bakes. For this reason avoid pressing the rhubarb into the batter, simply add it on top of it. STORING AND FREEZING This cake is best served on the day it is baked. It will keep for a couple of days in a covered container away from direct heat. You can also store it in the fridge, wrapped in foil. You can freeze the cake whole or in slices for up to three months, well wrapped. Thaw overnight in the fridge before serving.

Equipment

  • Electric hand mixer
  • Baking liners
  • Vanilla bean paste
  • Cake release
  • 9×13 rectangular cake tin

Nutrition

  • Calories287 kcal
  • Carbohydrates34 g
  • Protein4 g
  • Fat15 g
  • Saturated Fat4 g
  • Polyunsaturated Fat3 g
  • Monounsaturated Fat7 g
  • Trans Fat0.1 g
  • Cholesterol52 mg
  • Sodium173 mg
  • Potassium185 mg
  • Fiber1 g
  • Sugar19 g
  • Vitamin A658 IU
  • Vitamin C2 mg
  • Calcium77 mg
  • Iron1 mg