Sides · Irish

Mustard Champ

Sofia Romano

Recipe by Sofia Romano

Pasta & Mediterranean · October 10, 2026

Champ is the cozy Irish side you didn't know you needed: creamy mashed potatoes shot through with buttery scallions. Adding wholegrain mustard gives it a tangy, grown-up kick that plays beautifully with ham, pork, or a bubbling fish pie.

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Mustard Champ

Why you'll love this

  • Creamy, buttery comfort with a tangy mustard twist.
  • Comes together in about 30 minutes.
  • A side that goes with ham, pork, chicken, or fish pie.
  • Simple pantry ingredients, big flavor.

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 butter
  • 2 tablespoons wholegrain mustard
  • 1 bunch scallions, thinly sliced

Equipment

  • Large pot
  • Colander
  • Potato masher
  • Small saucepan
  • Skillet

Instructions

  1. Place 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 easily and the potatoes are fork-tender.
  2. Drain the potatoes well and return them to the warm pot, then mash until smooth with no big lumps left.
  3. In a small saucepan, warm the milk with half the butter (about 1 3/4 tablespoons) until the butter melts and the milk is steaming but not boiling.
  4. Beat the warm milk mixture into the mash along with the wholegrain mustard, stirring until the potatoes are light and creamy and the mustard is evenly swirled through.
  5. In a skillet, melt the remaining butter over medium heat and gently fry the sliced scallions for about 2 minutes, just until they soften but stay bright green and fresh looking.
  6. Fold the scallions and their buttery juices into the mash, season to taste with salt and pepper, and serve hot. It is excellent alongside ham or spooned over a fish pie.

Tips from the kitchen

  • Warm the milk before adding it so the mash stays hot and fluffy instead of turning gluey and cold.
  • Use a potato masher or ricer, not a food processor, which can make potatoes sticky and gummy.
  • Taste before serving: mustard varies in strength, so add a little more for extra punch if you like.

Estimated nutrition per serving: 290 cal · 6g protein · 42g carbs · 12g fat

Make it your own

  • Swap wholegrain mustard for Dijon for a smoother, sharper bite.
  • Stir in a handful of shredded cheddar for extra richness.
  • Use half-and-half instead of milk for an even creamier mash.

Storing & make-ahead

Keep 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 or all-purpose potatoes like russets or Yukon Golds mash up the fluffiest and soak up the butter and milk nicely.
Can I make it ahead?
Yes, make it up to a day ahead and reheat with a splash of warm milk to loosen it back up.
What's the difference between champ and colcannon?
Champ uses scallions stirred into mash, while colcannon adds cabbage or kale. This version adds mustard for extra flavor.
Can I leave out the mustard?
Absolutely. Skip it for classic champ, or use just a teaspoon if you want a milder tang.

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