Sides · Irish

Mustard Champ

Sofia Romano

Recipe by Sofia Romano

Pasta & Mediterranean · July 25, 2026

Champ is the ultimate Irish comfort side: creamy mashed potatoes shot through with buttery scallions. This version adds wholegrain mustard for a little tang and bite that keeps it from tasting flat. It comes together in about 30 minutes and works next to almost any dinner.

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Mustard Champ

Why you'll love this

  • Ready in about 30 minutes with pantry staples.
  • Mustard adds a tangy twist to classic mashed potatoes.
  • Goes with almost any main, from ham to fish.
  • Kid-friendly comfort food that feels a little special.

EveryDayMeal recipe

Mustard Champ

Prep
10m
Cook
20m
Total
30m
Serves
4
Level
Easy

Ingredients

  • 2 pounds potatoes, peeled and cut into chunks
  • 3/4 cup whole milk
  • 3 1/2 tablespoons unsalted butter
  • 2 tablespoons wholegrain mustard
  • 1 bunch scallions, thinly sliced
  • to taste salt and pepper

Equipment

  • Large pot
  • Colander
  • Potato masher or ricer
  • Small skillet

Instructions

  1. Put the potato chunks in a large pot, cover with cold salted water, and bring to a boil. Cook for about 15 minutes, until a knife slides in with no resistance, then drain well and let them steam dry for a minute so the mash stays fluffy.
  2. Mash the potatoes until smooth, or as chunky as you like. In the same pot or a small pan, warm the milk with half the butter (about 1 3/4 tablespoons) until the butter melts and the milk is steaming, which helps the mash stay hot and silky.
  3. Beat the warm milk mixture and the wholegrain mustard into the potatoes until creamy, then season generously with salt and pepper and taste as you go.
  4. Melt the remaining butter in a small skillet over medium heat and add the scallions. Cook for about 2 minutes, just until they soften but stay bright green, so they keep their fresh oniony snap.
  5. Fold the buttery scallions through the mash and serve hot. It is excellent alongside ham, sausages, or spooned over a fish pie.

Tips from the kitchen

  • Let the drained potatoes steam dry for a minute before mashing so they soak up the milk and butter instead of turning gluey.
  • Warm the milk before adding it: cold milk cools the mash and makes it stiff.
  • For extra smooth champ, use a potato ricer instead of a masher.

Estimated nutrition per serving: 270 cal · 5g protein · 38g carbs · 11g fat

Make it your own

  • Swap wholegrain mustard for Dijon for a smoother, sharper flavor.
  • Stir in a handful of shredded sharp cheddar for cheesy champ.
  • Use chives in place of scallions for a milder onion note.

Storing & make-ahead

Store leftovers in an airtight container in the fridge for up to 3 days. Reheat gently in a saucepan with a splash of milk, stirring, until hot and creamy again.

Good to know

What potatoes work best?
Starchy potatoes like russets give the fluffiest mash, but Yukon Golds work well for a creamier, buttery result.
Can I make champ ahead?
Yes. Make it up to a day ahead, refrigerate, and reheat with a little extra milk and butter to loosen it up.
Is champ the same as colcannon?
They are close cousins. Champ uses scallions, while colcannon adds cabbage or kale to the mash.
Can I use a different mustard?
Absolutely. Dijon or spicy brown both work; just start with less and taste, since some are stronger than others.

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