The Best Way to Rescue Leftover Veg: Homemade Cheese Sauce (No More Sad Side Dishes)

There are two types of leftover vegetables in this world: the ones you actually want to eat again… and the ones sitting in the fridge in a container you keep moving out of the way like it’s going to disappear on its own.

If you’ve got leftover carrots, broccoli, cauliflower, peas, green beans, sprouts, cabbage, leeks, sweetcorn, or even that “bit of everything” you served with Sunday lunch, I’ve got good news: you’re only one proper homemade cheese sauce away from turning them into something you’ll genuinely look forward to eating.

This is one of those simple kitchen tricks that feels like a cheat code. It’s warming, comforting, uses up odds and ends, and it’s far cheaper than throwing food away and starting again.

Let’s turn those leftovers into a bowl of pure comfort.

Why cheese sauce is the ultimate leftover vegetable upgrade

Leftover vegetables can be a bit… tired. They’ve already been cooked once, they’ve cooled down, and by the time you reheat them they can lean towards mushy or bland.

Cheese sauce fixes all of that.

It adds:

Creaminess and richness (instant comfort food energy)

Salt and savouriness (which most leftover veg needs)

A proper “meal” feel (not just a sad side dish)

A way to mix-and-match vegetables without thinking too hard

It also works brilliantly with vegetables that might not excite you on their own, like boiled carrots or leftover sprouts. Cheese makes everything feel intentional.

What leftover vegetables work best?

This idea is extremely forgiving, but some veg shine more than others.

Brilliant choices:

Broccoli

Cauliflower

Carrots

Leeks

Green beans

Peas

Sweetcorn

Cabbage (especially Savoy or white cabbage)

Brussels sprouts (yes, really!)

Also works well with:

Roasted veg like parsnips, squash, peppers, courgettes

Leftover mash mixed in for a thicker, almost “bake” texture

Cooked potatoes (instant cheesy potato bowl situation)

Just be careful with:

Very watery veg (like courgette cooked to death) — drain first

Salad-style leftovers (not the vibe here)

Easy homemade cheese sauce (the classic, proper way)

This is a simple béchamel base with cheese stirred in. It sounds fancy but it’s honestly easy once you’ve done it once.

Ingredients (serves 2–4 depending on how much veg you have)

25g butter

25g plain flour

300ml milk (any milk works, but semi-skimmed or whole is best)

150g mature cheddar, grated (or a mix of cheeses)

1 tsp Dijon mustard (optional but highly recommended)

Salt and black pepper

Optional extras: pinch of paprika, a tiny dash of Worcestershire sauce, or a little garlic powder

Method

Melt the butter in a saucepan over a medium heat.

Stir in the flour and cook for 1–2 minutes, stirring constantly. This cooks out the raw flour taste.

Add the milk slowly a splash at a time, whisking well as you go so it doesn’t go lumpy.

Once all the milk is in, keep stirring until thickened (it should coat the back of a spoon).

Lower the heat and stir in the cheese a handful at a time until melted.

Add mustard (if using), season with salt and pepper, and taste.

If it needs more “cheese flavour” rather than just creaminess, add a touch more cheddar.

That’s it. Proper homemade cheese sauce, done.

The best way to reheat leftover vegetables without ruining them

The golden rule: don’t boil them again.

Leftover veg has already been cooked, so you just want to warm it through gently.

Option 1: Stove-top (fastest)

Put your veg in a pan with a tablespoon of water

Cover with a lid

Heat for 2–3 minutes until hot

Then pour over the cheese sauce.

Option 2: Microwave (easiest)

Cover the veg (to stop drying out)

Heat in short bursts, stirring once

Then add the sauce on top.

Option 3: Oven bake (best for “proper meal” vibes)

Mix veg and cheese sauce together in an oven dish, top with extra cheese (and maybe breadcrumbs), then bake at 200°C (180°C fan) for 15–20 minutes until bubbling and golden.

If you want comfort food, this is the winner.

How to serve cheesy leftover veg (so it feels like dinner)

Cheese sauce turns vegetables into something you can build a meal around. Here are a few easy serving ideas:

1. On toast

Cheesy veg on thick toast is criminally underrated. Add a fried egg on top if you want to feel powerful.

2. With a jacket potato

Honestly one of the best combinations going. Add a bit of ham or leftover chicken if you want.

3. As a pasta bake shortcut

Stir cheesy veg into cooked pasta, top with more cheese, oven bake. Done.

4. With sausages or bacon

A tray of sausages and a side of cheesy veg feels like a “real dinner” with minimal effort.

5. In a toastie

Let the cheesy veg cool slightly, pile into a toastie with extra cheddar, and grill until crispy.

6. As a side to a roast dinner repeat

If you had a roast yesterday, you’ve basically got your next dinner sorted already.

Bonus: make it taste like proper pub food

If you want that “this is suspiciously good for leftovers” feeling, use one of these little flavour upgrades:

Mustard + mature cheddar (classic sharpness)

Add parmesan for an extra savoury hit

A pinch of smoked paprika for warmth

A dash of Worcestershire sauce (adds depth) or Henderson's Northern Relish

Blue cheese crumbled in for a rich, punchy sauce

A spoonful of cream cheese to make it extra silky

You don’t need all of them—just one makes it feel intentional.

What cheese works best?

Cheddar is the classic for a reason, especially mature cheddar, but you can mix and match depending on what’s in the fridge.

Great options include:

Mature cheddar (best all-rounder)

Red Leicester (beautiful colour, great flavour)

Gruyère (more “fancy bake” vibes)

Mozzarella (for stretch, but mix with something stronger)

Parmesan (strong, salty, brilliant in small amounts)

Avoid using only mild cheese unless you like a very gentle flavour. Leftover veg needs the boldness.

Storing and using up extra cheese sauce

Made too much sauce? That’s not a problem, that’s future-you being looked after.

Store in a sealed container in the fridge for up to 2–3 days

Reheat gently in a pan or microwave

Add a splash of milk and stir if it thickens too much

You can use it on:

Nachos

Pasta

Chips

Cauliflower cheese

Toasties

Anything you want to become a comfort meal

Final thought: leftovers aren’t boring, they’re a shortcut

Leftover vegetables don’t need to be the “meh” part of the meal you eat because you feel you should.

With a quick homemade cheese sauce, they become a proper, cosy, satisfying dish that feels like you planned it all along.

So next time you spot that box of leftover veg lurking in the fridge, don’t sigh… grab the butter, flour and cheese and turn it into something worth eating.

Because no vegetable deserves to die forgotten in a plastic tub.