A bake with Marmite in it
For autumn 2023, M&S put a Marmite product into their bakery range. Specifically: Pecan and Salted Caramel Blondies with Marmite. A blondie base (vanilla brownie), studded with pecans, with a Marmite-laced salted-caramel sauce swirled through, baked into a fudgy slab.
On the face of it: mad. In the eating: actually rather good. Worth understanding why, because this is the early experiment that led to M&S’s much bigger 2025 ambitions with the Marmite caramel sauce in the Christmas range (the M&S Christmas caramel range) and the pizza and mac-and-cheese line (the M&S pizza and mac-and-cheese range).
Why this works (the food-science footnote)
Marmite and caramel are chemical cousins. Both are products of Maillard-reaction browning, the chemistry that happens when sugars and proteins heat up together and produce the complex flavour molecules that we recognise as “browned” and “caramelised”. Marmite is, structurally, a deeply browned yeast extract. Caramel is a deeply browned sugar. The two have a lot of shared flavour compounds.
Salted caramel adds salt to caramel because salt makes sweetness more interesting. Marmite-caramel adds Marmite to caramel for the same reason but with a longer back-note: Marmite carries salt, glutamates, and a roasted depth that ordinary salted caramel does not.
So the M&S blondie was applying a piece of properly-grounded food science. It is not a stunt. It is a thoughtful flavour pairing dressed up as a slightly mad seasonal product.
The product itself
The blondies were sold in packs at around five pounds for two or three pieces. The Marmite was dosed conservatively (a thin swirl of salted-caramel sauce with Marmite mixed in, not a heavy hand). The pecan provided the textural element. The blondie base was properly fudgy, not the dry sponge-cake-pretending-to-be-a-blondie that lesser bakeries produce.
The flavour balance was the surprise. The Marmite was just-present, registering as a long savoury back-note rather than as a separate intrusive note. Most people I gave one to could not, on a blind tasting, identify what the secret ingredient was. Once told, they could taste it. Once tasted, they wanted another piece.
If you had asked me in September 2023 whether a Marmite blondie was a good idea, I would have said no. After eating one, I changed my mind. This is, in fact, the right reaction to most thoughtful sweet-savoury food experiments.
What it predicted
The 2023 blondie was M&S’s pilot project for using Marmite in their bakery and sweet-product range. The audience response was positive enough to justify a much more ambitious 2025 Christmas range with the Marmite caramel sauce, which itself is the direct descendant of the blondie’s caramel-Marmite swirl, just in a jar rather than baked into a pastry.
The same flavour logic applies to both products. The blondie was the small test. The caramel sauce is the scaled-up product. The Marmite-and-vanilla-ice-cream pairing that the caramel sauce enables is the dessert the blondie was a prototype for.
Are they still available
The 2023 autumn blondies were a seasonal product and disappeared from shelves by Christmas. They have not, to my knowledge, returned in subsequent years. The follow-up products (the 2025 caramel sauce, the various Marmite × M&S baked goods that have appeared in the food-to-go range) carry the same idea forward in different formats.
If M&S re-issue the blondie at some point in a future autumn range, get a pack. They are properly good. Bring one to a dinner party, do not tell anyone what is in it, and watch the reactions when you announce the ingredient at the end.
The Hate Party will refuse to try them on principle. The Hate Party are, in this case, missing a small piece of culinary fun.
Source: M&S Food autumn 2023 baking range; Guardian food pages contemporary coverage.
