Steak with Sweet Potato Mash

Steak and sweet potato mash are already good pals, but the honey mustard sauce is what gets everyone talking.

It’s sharp, sweet and creamy enough to drag through the mash, with garlicky green beans on the side for a bit of crunch.

The honey mustard sauce is the reason I kept thinking about this dinner afterwards.

It gets into the edges of the sliced steak, runs down into the sweet potato mash, and suddenly you’re chasing the last streaks of it around the plate with your fork.

The mash is mellow and buttery, which works ridiculously well against a sauce with a bit of mustard bite.

I keep the green beans fairly simple and cook them just until tender, because I want something fresh and snappy next to all that softness.

As for the steak, give it a properly hot pan and leave it alone long enough to get a dark crust before you start fussing with it.

Slice it, pile everything onto the plate, spoon over far more honey mustard sauce than you originally planned, and dinner is sorted.

 

Why You’ll Love This Recipe

• The steak stays juicy and tender with a beautiful seared crust.
• The sweet potato mash is smooth, creamy, and naturally a little sweet.
• Green beans add freshness and balance to the plate.
• The honey mustard sauce is glossy, savoury, and just slightly sweet.
• It feels impressive, but the steps are straightforward.
• It makes a lovely date-night dinner or a very solid treat-yourself meal.

Ingredients

For the steak

• 2 sirloin steaks, ribeye steaks, or strip steaks
• 1 tablespoon olive oil
• 1 tablespoon butter
• 1 teaspoon salt
• ½ teaspoon black pepper
• ½ teaspoon garlic powder

For the sweet potato mash

• 2 large sweet potatoes, peeled and chopped
• 2 tablespoons butter
• 3 to 4 tablespoons milk or cream
• Salt, to taste
• Black pepper, to taste

For the green beans

• 250g green beans, trimmed
• 1 tablespoon butter or olive oil
• Salt, to taste
• Black pepper, to taste

For the honey mustard sauce

• 1 tablespoon butter
• 1 small garlic clove, finely minced
• 2 tablespoons Dijon mustard
• 1 tablespoon honey
• 3 tablespoons chicken stock or beef stock
• 2 tablespoons cream
• ½ teaspoon black pepper

For finishing

• Extra cracked black pepper
• A few thyme leaves or chopped parsley, optional

How to Make Steak with Sweet Potato Mash and Green Beans

1. Cook the sweet potatoes

Start with the mash since that takes the longest.

• Add the chopped sweet potatoes to a saucepan.
• Cover with cold water and add a pinch of salt.
• Bring to a boil over medium-high heat.
• Cook for 15 to 20 minutes, or until the sweet potatoes are very tender.
• Drain well and return them to the warm pan.

Once they are drained, let them sit for a minute in the pan so any extra moisture can evaporate. That little pause helps the mash stay creamy instead of watery.

• Add the butter and 3 tablespoons of milk or cream.
• Mash until smooth.
• Season with salt and black pepper.
• Add another splash of milk if needed.

You want the mash soft and creamy, but still thick enough to hold the steak nicely on top.

2. Cook the green beans

While the sweet potatoes are boiling, get the green beans ready.

• Bring a small pot of salted water to a boil.
• Add the green beans and cook for 3 to 4 minutes, until tender but still bright green.
• Drain and set aside.

Right before serving, you will warm them in butter or oil so they taste properly finished and not like an afterthought.

3. Season the steak

Now for the part everyone actually gets excited about.

• Pat the steaks dry with kitchen paper.
• Rub both sides with the olive oil.
• Season with salt, black pepper, and garlic powder.

Drying the steak first makes a real difference. It helps you get that dark, savoury crust instead of a pale steamed surface.

4. Sear the steak

• Heat a heavy frying pan or skillet over medium-high to high heat.
• Add the steaks to the hot pan.
• Cook for 3 to 4 minutes on the first side.
• Flip and cook for another 3 to 4 minutes on the second side for medium-rare.
• Add the tablespoon of butter in the final minute and spoon it over the steaks.

If your steaks are thicker, give them another minute or so. If they are thinner, pull them a little earlier. You are aiming for a deep crust and a warm pink centre.

• Transfer the steaks to a plate.
• Loosely cover with foil.
• Let them rest for 5 to 10 minutes.

Do not skip the resting part. That is what keeps the steak juicy when you slice it.

5. Make the honey mustard sauce

Use the same pan so you keep all that flavour sitting in the bottom.

• Lower the heat to medium.
• Add 1 tablespoon of butter.
• Stir in the minced garlic and cook for about 20 to 30 seconds.
• Add the Dijon mustard, honey, stock, cream, and black pepper.
• Stir well until smooth.
• Let the sauce bubble gently for 2 to 3 minutes until lightly thickened.

The sauce should be glossy and spoonable. It does not need to be heavy or overly thick. It should settle nicely over the steak and pool a little into the mash.

6. Finish the green beans

• Add the cooked green beans to a small pan with the butter or olive oil.
• Toss over medium heat for 1 to 2 minutes.
• Season with a little salt and black pepper.

You just want them warmed through and lightly glossy.

7. Slice and plate

Now everything comes together.

• Spoon the sweet potato mash onto each plate.
• Top with the green beans off to one side.
• Slice the rested steak into thick pieces.
• Arrange the steak over the mash.
• Spoon the honey mustard sauce over the steak.
• Finish with cracked black pepper and a few thyme leaves or parsley if you like.

That final grind of black pepper really matters here. It sharpens up the rich sauce and gives the whole plate a little extra punch.

Tips for the Best Result

Use a good steak

You do not need the most expensive cut in the world, but pick one with decent marbling and good thickness. Thin steaks cook too fast and do not give you the same juicy sliced finish.

Don’t overwork the mash

Mash the sweet potatoes until smooth, but stop once they are creamy. Overmixing can make mashed potatoes gluey, and while sweet potatoes are more forgiving, they still taste best when kept simple.

Keep the green beans bright

Do not cook them to death. They should be tender, yes, but still have a little life left in them.

Taste the sauce before serving

Some mustard brands are sharper than others. If yours tastes too punchy, add a tiny bit more cream or a small extra drizzle of honey.

Serving Ideas

This plate is already a full meal, so it honestly does not need much else. If I were serving it for guests, I might add a simple glass of red wine and call it a night. A bit of crusty bread would also be nice if you want something to drag through the extra sauce. If you want to brighten the meal even more, a quick leafy salad with a sharp vinaigrette would work well on the side.

Storage

If you have leftovers, store everything in separate airtight containers in the fridge for up to 3 days.

• Reheat the mash gently on the hob or in the microwave with a splash of milk.
• Warm the green beans in a pan for a minute or two.
• Reheat the steak gently so it does not overcook.
• Warm the sauce separately and stir before serving.

The steak is at its best fresh, but leftovers still make a very good lunch the next day.

Frequently Asked Questions

Can I use another cut of steak?

Yes. Sirloin, ribeye, strip steak, or rump all work well. Just adjust the cooking time depending on thickness.

Can I make the mash ahead of time?

Absolutely. Make it earlier in the day, then reheat it with a splash of milk or cream to loosen it back up.

What if I do not like sweet potatoes?

You can swap them for regular mashed potatoes, but the sweet potato mash really gives this plate its lovely contrast.

Is the sauce very sweet?

No, not at all. The honey softens the mustard and rounds it out, but the sauce still leans savoury.

How do I know when the steak is done?

For medium-rare, the centre should still be pink and juicy. If you use a thermometer, aim for around 54 to 57°C before resting.

Can I use tenderstem broccoli instead of green beans?

Yes, that would work beautifully. Asparagus would be lovely too.

 

Final Thoughts

This is one of those dinners that looks like you planned it carefully, even if you really just wanted something delicious and comforting on a random evening.

The steak is juicy, the sweet potato mash is silky and rich, and the green beans bring exactly the freshness the plate needs.

Then that glossy honey mustard sauce lands on top and makes everything taste even better than it already did.

It is simple food, but done in a way that feels a little elevated. And honestly, that is usually the sweet spot.