Rhubarb & Custard Cake is a moist, fruity Brit classic with a velvety Earl Grey custard glaze. This recipe balances tart rhubarb’s acidity with sweet custard, while tea-infused topping adds floral depth without bitterness.
| Prep Time | 20 min |
|---|---|
| Cook Time | 45-55 min |
| Total Time | 65-75 min |
| Servings | 8 |
| Difficulty | Moderate |
| Cuisine | British |
Why This Recipe Works
The rhubarb layer caramelizes while baking, creating a natural syrup that soaks into the cake’s crumb without making it soggy. Blending custard powder directly into the batter ensures even distribution, while chilled soured cream keeps the texture tender.
Using tea bags in the custard (not steeped) prevents over-extraction of tannins that would overpower the milk. The cake benefits from resting completely before inverting – I’ve ruined several batches by impatiently flipping them too early.
Ingredients
| Ingredient | Quantity | Notes |
|---|---|---|
| Unsalted butter | 175g + extra | Room temperature yields smoother creaming |
| Caster sugar | 175g + 2 tbsp | For rhubarb caramel; sub brown sugar for deeper flavor |
| Forced rhubarb | 400g | Less woody than regular rhubarb; frozen works |
| Free-range eggs | 3 medium | Room temp ensures better air whisking |
| Self-raising flour | 175g | Clafoutis-style thickening requires light folding |
Step-by-Step Instructions
Prepare Tin & Rhubarb Layer
- Preheat oven to 180°C, gas mark 4
- Line 20cm springform tin with parchment and butter sides
- Place 1 tbsp sugar in base and shake to spread evenly
- Trim rhubarb into 2.5cm sticks and arrange in single layer
- Sprinkle remaining 1 tbsp sugar over rhubarb and set aside
Make the Cake Batter
- Cream butter and 175g sugar for 3-4 minutes until pale and fluffy
- Add eggs one at a time, beating well after each addition
- Sift in flour, custard powder, and sea salt; gently fold in
- Stir in 100g chilled soured cream for moisture
- Scrape batter into prepared tin, spreading to cover rhubarb
Bake the Cake
- Bake 45-55 minutes until top springs back when lightly touched
- Skewer should come out mostly clean with just a few crumbs
- Cool completely in pan (at least 45 minutes) before inverting
- Transfer to serving plate with rhubarb side up
Make the Custard
- Simmer milk, tea bags, and vanilla until steaming hot
- Discard tea bags and whisk 35g custard powder with 1 tbsp milk
- Add to remaining milk and cook 2-3 minutes until thickened
- Cool on rack 30 minutes before tempering and serving
Chef Tips for Perfect Results
- Chill soured cream for 30 minutes before adding to batter
- Bake cake on middle rack for even heat distribution
- Don’t skip the parchment lining – rhubarb sticks easily
- Temper custard by whisking in 100ml warm milk before adding to cold custard powder
Common Mistakes to Avoid
- Overmixing batter after adding flour (destroys delicate crumb)
- Opening oven during first 30 minutes of baking (sinks middle)
- Using instant custard powder – this recipe specifically requires standard cornstarch-based varieties
- Removing cake while still warm (causes custard mix to pool unevenly)
Variations and Substitutions
| Ingredient | Substitute | Impact |
|---|---|---|
| Caster sugar | Brown sugar | Adds caramel flavor and denser texture |
| Unsalted butter | Cake margarine | Slight reduction in fat but maintains spreadability |
| Vanilla bean paste | Plain vanilla extract | One-to-one substitution |
Serving Suggestions and Pairings
- Serve with clotted cream and vintage teacups for afternoon tea
- Pair with a strong cheddar to contrast the sweet tartness
- For garden parties, slice with fresh mint leaves and edible flowers
- Set custard separately in ramekins for individual dipping
Storage and Reheating
| Method | Duration | Instructions |
|---|---|---|
| Airtight container | 5 days | Cover with parchment before storing |
| Freezer | 2 months | Flash-freeze on wire rack first |
| Reheating | 10 minutes | Bake at 160°C with 25ml milk added |
Nutritional Information
| Per Serving | Amount |
|---|---|
| Calories | 420 kcal |
| Protein | 6g |
| Fat | 24g |
| Carbohydrates | 51g |
| Sugar | 35g |
| Sodium | 280mg |
| Notes | Approximate values. Variations in egg size and rhubarb water content affect totals. |
Frequently Asked Questions
Can frozen rhubarb be used?
Yes, thaw and pat dry to remove excess moisture. Frozen rhubarb usually requires less sugar as it’s less tart when raw.
Why does my cake fall apart when flipping?
Insufficient cooling time allows custard mixture to seep into layers. Let it cool completely in pan before inverting.
Can I use a different tea for the custard?
Peppermint or earl grey work, but avoid black teas with strong astringent tannins that will sour the custard.
How to tell if the cake is properly cooked?
The sides should pull away from pan, and a skewer should come out with wet crumbs, not raw batter.
What if I forget the custard powder in the cake?
Blend 20g into batter’s final mix and reduce cooking time by 10 minutes to prevent overbaking.
Rhubarb & Custard Cake is Britain’s answer to Apple Pie – a dessert with deep heritage and endless variation possibilities. Master the rhubarb layer technique first, then experiment with flavors like caramel custard or lavender-infused chocolate versions. This recipe requires patience but delivers restaurant-quality results when temperature and timing are precise.
Print
Rhubarb & Custard Cake with Earl Grey Custard Glaze
- Total Time: 75
- Yield: 8 slices 1x
- Diet: Vegetarian
Description
A moist British classic where tart rhubarb is balanced with sweet custard, complemented by a floral Earl Grey custard glaze. Perfect for tea lovers and dessert aficionados.
Ingredients
175g unsalted butter (room temperature), plus extra for greasing
175g caster sugar
2 tbsp caster sugar (for rhubarb)
400g forced rhubarb
3 medium free-range eggs (room temperature)
175g self-raising flour
35g custard powder
Pinch of sea salt
100g chilled soured cream
300ml milk
2 used Earl Grey tea bags (not steeped)
1 tsp vanilla extract
Instructions
Preheat oven to 180°C (gas mark 4)
Line a 20cm springform tin with parchment and butter the sides
Place 1 tbsp caster sugar in the base of the tin and shake to spread
Trim the rhubarb into 2.5cm sticks and arrange in a single layer
Sprinkle the remaining 1 tbsp caster sugar over rhubarb and set aside
In a mixing bowl, cream 175g butter and 175g caster sugar for 3-4 minutes until pale and fluffy
Add eggs one at a time, beating well after each addition
Sift in flour, custard powder, and sea salt; gently fold in
Stir in chilled soured cream
Scrape the batter into the prepared tin and spread it to cover the rhubarb
Bake for 45-55 minutes until the top springs back when lightly touched
Check with a skewer – it should come out mostly clean with just a few crumbs
Cool completely in the tin (at least 45 minutes) before inverting the cake onto a serving plate
To make the glaze, simmer milk, tea bags, and vanilla extract until steaming hot
Remove tea bags and whisk 35g custard powder with 1 tbsp chilled milk
Add the custard powder mixture to the hot milk and stir until smooth and shiny
Allow glaze to cool slightly before drizzling over the top of the cooled cake
Serve slightly warm or at room temperature
Notes
Forced rhubarb is less woody and ideal for this recipe; frozen rhubarb can be used as a substitute
Room temperature eggs are easier to whip and blend into the batter
Chilling the soured cream ensures a tender crumb
Letting the cake cool completely in the tin is essential to avoid collapsing when inverting
For deeper flavor, brown sugar can be substituted for caster sugar in the rhubarb mixture
- Prep Time: 20
- Cook Time: 55
- Category: Desserts
- Method: Baking
- Cuisine: British
Nutrition
- Serving Size: 1 slice
- Calories: 420
- Sugar: 50g
- Sodium: 180mg
- Fat: 20g
- Saturated Fat: 12g
- Carbohydrates: 55g
- Fiber: 2g
- Protein: 6g
- Cholesterol: 60mg
