Mary Berry Celeriac and Potato Mash

This mash is what I make when plain potatoes just won’t cut it—when the roast’s a little fancier, or I need something that tastes rich without adding double cream or gravy. The celeriac brings a mellow, nutty warmth that makes you wonder why we ever stopped at just potatoes in the first place.

The first time I made it, I didn’t blend the celeriac properly and ended up with strange, chewy chunks lurking in a sea of fluffy potato. Lesson learned: hot veg, thorough mashing, and plenty of seasoning. Now it’s my go-to with slow-cooked beef, roast chicken, or even just a fried egg on top.

WHAT MAKES THIS RECIPE SPECIAL

This isn’t just mash—it’s elevated mash. It’s still weeknight-easy, but with a touch of “restaurant side dish” energy. Here’s what makes it work:

• Crème fraîche instead of cream – Adds richness and a lovely tang.
• Two mashes in one – Potato gives fluff, celeriac gives depth.
• You can make it ahead – Holds up well and reheats beautifully with a splash of milk.

INGREDIENTS + WHY THEY MATTER

• Floury Potatoes (1kg) – King Edward or Maris Piper. They mash up smooth and fluffy.
• Butter (a knob) – Adds silkiness. I use unsalted so I can control the seasoning.
• Celeriac (2 large) – Peeled and cubed. Earthy, slightly sweet, and balances the starch.
• Crème Fraîche (200ml) – Full-fat. Tangy, creamy, and gives a fresher flavour than cream.
• Salt + Black Pepper – Don’t hold back. Mash needs proper seasoning to come alive.

MAKING IT YOURS (WITHOUT RUINING IT)

• No crème fraîche? Sour cream works. Or mix cream + lemon juice as a cheat.
• Add herbs? Chopped chives or parsley stirred in right before serving works well.
• Going dairy-free? Use olive oil in the mash and dairy-free yoghurt in place of crème fraîche.
• Fancy finish? Dot with browned butter and a pinch of nutmeg.

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

WHAT WENT WRONG	WHY IT HAPPENS	HOW TO FIX IT
Mash was lumpy	Celeriac wasn’t blended hot	Mash both while hot; blend celeriac thoroughly
Watery texture	Overcooked the celeriac	Simmer only until just tender, then drain well
Tasted bland	Didn’t season enough	Salt in layers—during boiling and mashing
Turned gluey	Used waxy potatoes or overmixed	Stick to floury spuds and mash gently

HOW TO MAKE MARY BERRY’S CELERIAC AND POTATO MASH

Boil the Potatoes
Place cubed potatoes in a pan of cold salted water. Bring to the boil and simmer 15 mins or until fork-tender. Drain well. Mash or pass through a ricer. Stir in a knob of butter, season with salt and pepper.

Cook the Celeriac
In a second pan, cook the cubed celeriac in salted water until tender (about 15 mins). Drain, then blend with a hand blender or food processor until smooth. Stir in the crème fraîche.

Combine
Fold the celeriac purée into the potato mash. Mix gently but thoroughly. Taste and adjust seasoning.

Serve
Serve warm, with extra butter or herbs if you like.

TIPS FROM MY KITCHEN

• I always mash everything while it’s still steaming—cold mash is lumpy mash.
• If the celeriac’s really knobbly, I peel it with a knife instead of a peeler—much easier.
• I sometimes warm the crème fraîche slightly before adding, just so it blends in better.
• Freezes well in portions—great for batch cooking.

STORAGE + SERVING

Fridge: Keeps 2 days in a sealed container.
Freezer: Freeze in tubs or bags for up to 1 month.
Reheat: On the hob with a splash of milk or butter, or in the microwave, stirring halfway.
Serve with: Roasts, sausages, stews, or anything with gravy.

FREQUENTLY ASKED QUESTIONS

Q: Can I make this ahead of time?
Yes—it reheats beautifully. Just add a splash of milk and stir as you warm it.

Q: Can I skip the potatoes?
You can, but it’ll be stronger and more fibrous. Half-and-half gives the best balance.

Q: What’s the best way to blend celeriac?
Stick blender or food processor. Masher won’t get it smooth enough on its own.

Q: Can I use milk instead of crème fraîche?
You can, but it won’t have the same tang. Add a splash of lemon juice to help.

Try More Recipes:

• Mary Berry Fish Pie With Crushed Potatoes​
• Mary Berry Cauliflower Potato Cakes Recipe
• Mary Berry Posh Jacket Potatoes