Equipment
Ingredients
Potatoes
- 1000 g yukon gold potatoes, whole, unpeeled
- 2000 ml water, cold tap water
- 15 g fine sea salt
Dairy and Seasonings
- 75 g unsalted butter, cubed, chilled
- 100 ml whole milk
- 60 ml heavy cream
- 45 g wholegrain mustard, prepared, whole seed
- 4 g fine sea salt
- 1 g ground black pepper, freshly cracked
- 10 g fresh chives, finely sliced
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 393 kcal
- Protein
- 8 g
- Carbohydrates
- 50 g
- Fat
- 23 g
- Sugar
- 5 g
- Saturated Fat
- 14 g
- Zinc
- 0.8 mg
- Vitamin A
- 203 mcg
- Vitamin C
- 47 mg
- Water
- 34 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Peel 1000g of Yukon Gold potatoes with a vegetable peeler, trimming away any eyes or surface blemishes to yield roughly 880g of prepared potato.
Cut the peeled potatoes into uniform 3 cm chunks on a cutting board using a chef knife to promote equal cooking rates.
Place the cut potatoes into a large saucepan, pour in 2000 ml cold water and 15g fine sea salt, and bring to a boil over medium-high heat.
Lower the heat to maintain a steady simmer and cook the potatoes uncovered for 15 to 20 minutes until completely tender throughout.
Empty the contents of the saucepan into a colander set in the sink to drain all cooking water thoroughly.
Return the drained potatoes to the empty large saucepan set over low heat for 1 to 2 minutes, shaking the pot gently to steam off residual surface moisture.
Warm 100 ml whole milk and 60 ml heavy cream together in a small saucepan over medium heat to 65°C (149°F), removing before it comes to a boil.
Pass the hot, dried potatoes through a potato ricer directly back into the warm large saucepan.
Add 75g chilled cubed unsalted butter to the riced potatoes and stir with a silicone spatula until fully melted and integrated.
Pour the warm milk and cream mixture into the potatoes in two additions, folding gently with the silicone spatula until smooth and glossy.
Fold in 45g wholegrain mustard, 4g fine sea salt, and 1g freshly ground black pepper until the seeds and seasonings are evenly dispersed.
Spoon the mashed potatoes into a warm serving bowl and scatter 10g finely sliced fresh chives across the surface before serving.
Chef's Notes
- Starting potatoes in cold, well-salted water ensures the interior and exterior cook at an identical rate, preventing the outside from waterlogging before the core turns soft.
- Steam-drying the drained tubers on the low burner removes surface moisture so the hungry starch cells absorb butter fat rather than residual water.
- Warm dairy prevents temperature shock; adding cold milk directly to hot mashed potatoes chills the starch, resulting in a dull, stiff mouthfeel.
- Wholegrain mustard provides both textural pop and mild acetic tang, which cuts cleanly through the unctuous butter and cream.
Storage
Refrigerator: 3 days — Cool promptly and seal in an airtight container within two hours of preparation.
Freezer: 1 month — Freeze in an airtight container. Starch retrogradation may cause slight weeping upon thaw; beat vigorously while reheating.
Reheating: Reheat on the stovetop over low heat or in a microwave, stirring frequently, until thoroughly steaming and reaching a minimum internal temperature of 74°C (165°F).
Troubleshooting
Mash turns gluey and sticky instead of fluffy
Cause: Potatoes were overworked mechanically, releasing excessive free starch into the emulsion
Fix: Cannot be fixed completely; gently fold in an additional 20 ml warm cream and 15g melted butter to soften the texture
Prevention: Use a potato ricer rather than a blender or food processor, and gently fold liquids just until absorbed
Mash tastes watery and lacks rich potato flavor
Cause: Potatoes absorbed excessive boiling water and were not dried out before ricing
Fix: Warm the riced mixture over very low heat for 2 minutes before incorporating butter and liquid
Prevention: Always perform the stovetop steam-drying step for 1 to 2 minutes after draining
Mustard pungency overwhelms or tastes unpleasantly bitter
Cause: Mustard was simmered over direct heat, burning volatile aromas and releasing bitter tannins from seed coats
Fix: Stir in an extra 15g cold unsalted butter or 20 ml warm heavy cream to coat the palate and soften the acidity
Prevention: Fold the mustard in off the heat at the very end of assembly
Cultural Context
Mustard mash is a foundational offering across contemporary British and Irish pub cuisine, serving as a textural modernization of classic champ or colcannon. It is traditionally paired with rich, roasted proteins such as braised pork sausages, roast beef, or slow-cooked lamb shanks.
