This slow cooker 3-ingredient poor man's mustard potatoes recipe came to me the way all the best budget dishes do: from a neighbor over the fence. She told me it was her dad’s old factory-lunchbox favorite, thrown together on tight weeks when money was thin but everyone still needed a hot, comforting meal. I was honestly shocked how much flavor you get from just potatoes, mustard, and a little fat. The long, slow cooking turns simple pantry staples into golden chunks with crispy caramelized edges and a tangy, creamy mustard glaze that tastes like you fussed for hours, even though the slow cooker does all the work.
These mustard potatoes are hearty enough to be the star on a plate with just a simple green salad or some steamed green beans on the side. They’re also wonderful next to grilled or pan-fried sausages, pork chops, or roast chicken. If you’re really stretching the grocery budget, serve them in bowls with a fried egg on top and a handful of frozen peas or corn for color. A slice of buttered bread or toast to mop up the extra mustardy glaze makes this feel like a complete, cozy meal.
Slow Cooker 3-Ingredient Poor Man's Mustard Potatoes
Servings: 4

Ingredients
2 1/2 pounds russet or Yukon Gold potatoes, scrubbed and cut into 1 1/2-inch chunks
1/2 cup prepared yellow mustard
1/4 cup neutral cooking oil or melted butter (such as vegetable oil, canola oil, or salted butter)
1 teaspoon salt (optional but recommended, use what you have)
1/2 teaspoon black pepper (optional, if you keep it on hand)
2 tablespoons water (only if needed to loosen the mustard mixture)
Directions
Lightly grease the inside of your slow cooker crock with a bit of oil or butter to help prevent sticking and make cleanup easier.
Scrub the potatoes well and cut them into roughly 1 1/2-inch chunks. You can peel them if your family prefers, but leaving the skins on adds texture and saves time and money.
In a medium bowl, whisk together the yellow mustard and the oil or melted butter until it looks smooth and a little creamy. If it seems very thick or stiff, whisk in 1–2 tablespoons of water just to make it easier to coat the potatoes.
Sprinkle the salt and pepper (if using) over the mustard mixture and stir to combine. Taste a tiny dab—this should be a bit saltier and tangier than you’d normally eat straight, because it will mellow as it coats the potatoes and cooks.
Add the potato chunks to the slow cooker. Pour the mustard mixture over the top, using a spatula to scrape out every bit so nothing goes to waste.
Use a large spoon to gently toss the potatoes right in the slow cooker until every piece is well coated in the mustard mixture. Try to get the potatoes into as even a layer as possible so they cook at the same rate.
Cover the slow cooker with the lid and cook on HIGH for 3 to 4 hours, or on LOW for 6 to 7 hours, until the potatoes are very tender when pierced with a fork and some edges are starting to look browned and caramelized.
Once the potatoes are tender, give them a gentle stir. Some pieces will break a little and release their fluffy insides, which helps thicken the mustard glaze and makes it cling to every chunk.
If you’d like a few extra crispy bits (this is where the magic really tastes like more than three ingredients), leave the lid slightly ajar for the last 20 to 30 minutes of cooking on HIGH so a bit of steam can escape. Stir once or twice so more surfaces get a chance to caramelize against the sides and bottom of the crock.
Taste and adjust the seasoning with a pinch more salt or pepper if needed. Spoon the hot mustard potatoes onto a plate or into a shallow bowl, making sure to scoop up some of the tangy yellow glaze from the bottom of the slow cooker. Serve warm.
Variations & Tips
To keep this true to its working-class roots, I like to stick to the three essentials—potatoes, mustard, and fat—and then only add extras if the pantry allows. For a milder flavor for picky eaters, use half yellow mustard and half water or a splash of milk, or stir in a spoonful of mayonnaise at the end to soften the tang. If your kids like things a little cheesy, you can sprinkle a handful of shredded cheese over the hot potatoes right before serving and let it melt into the mustard glaze. For a smoky twist, add a pinch of smoked paprika or a chopped cooked hot dog or sausage if you have one leftover from another meal. Yukon Gold potatoes give a creamier, buttery bite, while russets get fluffier and soak up more mustard; use whichever is on sale. If you’re cooking ahead, you can prep the potatoes and mustard mixture the night before, keep them in the fridge separately, then toss together in the morning and start the slow cooker. For food safety, always wash and scrub potatoes well to remove dirt, trim away any green spots or large sprouts, and discard any potatoes that smell off. Keep the slow cooker covered during cooking and avoid lifting the lid too often so the potatoes reach a safe, steady temperature. Once cooked, refrigerate leftovers within 2 hours in a shallow container and eat within 3 to 4 days, reheating until steaming hot all the way through. If reheating in the microwave, stir halfway for even heating. Avoid leaving the slow cooker on “warm” for more than 4 hours after cooking, especially if the lid is off, to prevent bacteria growth.