Large Batch Caramelised Onions (Perfect for Freezing)

These slow-cooked caramelised onions are sweet, rich, and deeply savoury — the kind of kitchen staple that instantly upgrades everything from sandwiches to sauces. Make a big batch, freeze in portions, and you’ll always have incredible flavour ready to go.

Ingredients

6 large yellow onions, thinly sliced

2 x 1-inch knobs of butter

Drizzle of olive oil

Sea salt & cracked black pepper

2 bay leaves

1/3 cup muscovado sugar

Method

1. Start low and slow

In a large, heavy-based pan, melt the butter with a drizzle of olive oil over medium-low heat.

Add the sliced onions and toss to coat.

2. Season and soften

Add a generous pinch of salt and cracked black pepper, along with the bay leaves.

Cook gently on low, stirring occasionally, until the onions soften and begin to break down (about 15–20 minutes).

3. Build the colour

Once softened, add the muscovado sugar and stir well.

Continue cooking on low heat, stirring regularly, until the onions turn a deep golden brown and develop a jammy texture.

This can take 30–45 minutes total — don’t rush it

4. Finish

Remove the bay leaves and taste for seasoning. Adjust salt if needed.

You’re looking for onions that are:

deeply golden

soft and sticky

rich, not burnt

Freezer Prep

Let the onions cool completely, then transfer into containers or portion into small batches.

Freeze in:

ice cube trays (for small flavour boosts)

½ cup portions (perfect for cooking)

They’ll keep well in the freezer and can be used straight from frozen.

Ways to Use

Stir into ragu or pasta sauces

Add to grilled cheese or quesadillas

Spread on toast with cheese or hummus

Fold into eggs or omelettes

Top your burgers

Add to cooked pizzas

Tips

Low heat = best flavour (high heat will burn before they caramelise)

A mix of butter and oil prevents burning and adds richness

Muscovado sugar enhances depth, but don’t overdo it — onions should still be the star

Why This is a Game-Changer

Having caramelised onions ready in your freezer means you can:

skip 45 minutes of cooking

add instant depth to any dish

make simple meals taste restaurant-quality