Mary Berry Butterscotch Cake

Right, I’ll be honest: this cake nearly didn’t happen. I was halfway through whisking when I realised I’d used fridge-cold margarine and forgotten to soften the butter for the icing. Classic me. But guess what? That cold marg actually saved the sponge.

I first made this Butterscotch Traybake from Mary Berry’s Fast Cakes on a grey Sunday when I needed something sweet but couldn’t face a faff. It’s the sort of cake that looks humble but vanishes within hours. The crumb is soft, the crust just golden, and the icing? A buttery, fudgey dream that tastes like school dinner puddings—if the dinner lady had gone to Le Cordon Bleu.

Let me show you how I fixed my icing disaster, got the sponge bang on, and why this one’s now my go-to for bake sales, birthdays, and “just because” bakes.

Why This One Works So Well

There’s real magic in this method—everything gets thrown in one bowl, mixed, and baked. No creaming, no fuss. But here’s what really makes it sing:

• Cold margarine gives a tender crumb without greasiness. I didn’t expect this, but when I tried it with softened butter instead, the cake turned oddly dense.
• Light muscovado sugar adds a rich butterscotch depth you just can’t fake. Caster sugar? Too flat. Dark brown? Too heavy.
• And the traybake format makes it practically un-mess-up-able. No sunken centres, no worrying if the middle’s raw.

Most butterscotch cakes lean too sweet or dry. This one’s balanced, golden, and—if you get the icing right—absolutely lush.

INGREDIENTS + WHY THEY MATTER

• Cold margarine (225g) – Yep, straight from the fridge. It gives the batter body and a soft, light finish. (I once used spreadable butter… big mistake. Cake turned oily.)
• Light muscovado sugar (225g) – The hero. Gives a gentle toffee flavour and keeps the sponge moist.
• Eggs (4 large) – Binds and lifts. I tested with medium eggs once—too dry.
• Self-raising flour (225g) – No need to add extra raising agents apart from…
• Baking powder (1 tsp) – Just enough to help it rise that little bit more.

For the icing:

• Butter (114g, softened) – This is where I slipped up. If it’s too cold, the icing won’t cream. I’ve since started cubing it and leaving it out while the cake cools.
• Confectioners’ sugar (175g) – Sweetness and structure.
• Light muscovado sugar (25g) – Game-changer. Adds a chewy, caramelly note to the icing.
• Vanilla (1 tsp) – Rounds out the sweetness.
• Milk (2 tbsp) – Softens and loosens the icing.

Making It Yours (Without Ruining It)

I’ve tested a few cheeky swaps—some work, some don’t:

• No margarine? Use block butter chilled from the fridge. Not spreadable.
• Egg-free? I tried with 4 tbsp apple sauce as a swap. It worked, just a bit denser.
• Gluten-free? Use a 1:1 GF blend with xanthan gum. I tried Doves Farm plus ½ tsp extra baking powder. Cake was slightly crumbly but tasty.
• Nutty twist? Add 75g chopped pecans to the batter—lovely crunch and richness.

Avoid dark muscovado sugar. Overpowers everything. Trust me, I tried.

MISTAKES I’VE MADE (AND HOW TO AVOID THEM)

What Went Wrong	Why It Happens	How to Fix It
Icing turned gritty	Butter too cold or sugar not mixed in	Use softened butter and whisk a full 2 mins
Cake sank in middle	Overmixed or oven too hot	Beat until just fluffy, check oven temp
Sponge felt greasy	Used spreadable butter	Stick with block margarine or real butter
Edges dried out	Overbaked by 5 minutes	Check at 25–28 mins, not just at 30

HOW TO MAKE MARY BERRY’S BUTTERSCOTCH CAKE

1. Preheat your oven to 180°C (160°C fan) / 350°F. Line a 30x23cm traybake tin with nonstick baking paper.
2. In a large bowl, add cold margarine, muscovado sugar, eggs, self-raising flour, and baking powder.
3. Beat with an electric mixer for 1–2 minutes until smooth and fluffy. Batter should be soft but thick, like soft-serve ice cream.
4. Scoop into the tin, level with a spatula, and tap the tray gently to release air bubbles.
5. Bake for 28–30 minutes until golden brown and pulling slightly from the edges.
6. Cool completely in the tin. (Warm cake plus icing equals disaster. I learned the hard way.)
7. Make the icing: Beat softened butter with icing sugar, muscovado sugar, vanilla, and milk until smooth, creamy, and spreadable.
8. Spread icing evenly, using a warm spoon to smooth the top.
9. Slice into 24 squares. Try not to eat four before serving. I failed.

TIPS FROM MY KITCHEN

• I weigh everything, even liquids. It’s more accurate—and Mary would approve.
• My fan oven runs hot, so I check the cake at 25 mins.
• I use a palette knife dipped in warm water to spread the icing smooth.
• Want sharp cuts? Chill the cake before slicing—it firms up the icing.

STORAGE + SERVING

• Keeps: 4–5 days in an airtight tin (not fridge—it makes the sponge go firm).
• Freezes: Beautifully. Wrap squares individually, freeze up to 3 months.
• To serve: Lovely with whipped cream or a drizzle of caramel sauce. Or just a cuppa. Yorkshire Gold is my usual.

FAQs – REAL BAKING QUESTIONS, ANSWERED

Q: Can I use butter instead of margarine?
A: You can, but it must be fridge-cold block butter. Softened or spreadable butter gives a greasy sponge.

Q: Why is there muscovado sugar in the icing?
A: It gives that chewy, toffee-fudge flavour. Don’t skip it—it’s what makes the icing special.

Q: My cake is too sweet. Can I reduce the sugar?
A: I tested with 25g less sugar—sponge was fine, but icing needs the full amount to set properly.

Q: Can I bake this as a round cake?
A: I tried it in two 8-inch tins. It worked. Just reduce the bake time to 22–25 minutes.

Q: What’s the texture like?
A: Soft, light, and a bit fudgy. Not dense, but not airy either—just right for a traybake.

Try More Recipes:

• Mary Berry Madeira Cake
• Mary Berry Butterfly Cakes
• Mary Berry Coconut Meringue Slices
• Mary Berry Malted Chocolate Cake