Banana Syrup for Coffee: The 3-Ingredient Recipe

Banana syrup for coffee is one very ripe banana, one cup of sugar and one cup of water, simmered gently for ten minutes and strained. It tastes the way a banana latte should, keeps for two weeks in the fridge, and costs a few cents a pump instead of the dollar a café adds for the flavour shot.

Why banana works in coffee

Banana is one of the few fruit flavours that genuinely belongs next to espresso. Coffee already has caramel and dried-fruit notes, and a ripe banana sits in the same family: sweet, a little bready, faintly floral. Banana bread is popular for the same reason. The trick is getting that flavour into a syrup without the mush, and without the grey-brown colour that a boiled banana leaves behind.

Two things decide whether the syrup tastes like a banana or like banana sweets. First, the banana has to be properly ripe, brown-spotted and soft, because that is when the starch has turned into sugar and the aroma is at its peak. Second, the syrup should be simmered, never boiled hard. A rolling boil caramelises the sugar and cooks the fruit, and both push the flavour toward toffee and away from fresh banana.

Ingredients

For about 300 ml of syrup, enough for 20 to 25 drinks:

Ingredient	Amount	Notes
Very ripe banana	1 medium (about 120 g peeled)	Brown spots all over, soft to the touch
Granulated sugar	200 g (1 cup)	White sugar keeps the colour light; brown sugar tastes of toffee
Water	240 ml (1 cup)	Filtered if your tap water tastes of chlorine
Fine salt	a small pinch	Optional, rounds out the sweetness
Vanilla extract	half a teaspoon	Optional, adds a “banana bread” note

You also need a small saucepan, a wooden spoon, a fine sieve, and a clean bottle or jar with a lid. A paper coffee filter is useful if you want the syrup clear.

Method

1. Peel and slice the banana into a small saucepan. Add the sugar and water.
2. Set the pan over medium-low heat and stir until the sugar has dissolved. This takes two or three minutes.
3. Bring the mixture to a gentle simmer, small bubbles rather than a boil, and let it cook for eight to ten minutes. Press the banana slices against the side of the pan with the spoon once or twice, but do not mash them into a purée; you want the flavour in the syrup, not the fibre.
4. Take the pan off the heat. Stir in the salt and vanilla if you are using them.
5. Leave the pan to stand for ten minutes so the banana keeps steeping while the syrup cools slightly.
6. Pour through a fine sieve into a jug. Do not press the solids; let gravity do the work, or the syrup will be cloudy.
7. For a clear, golden syrup, pour it a second time through a paper coffee filter. This is slow, around ten minutes, but it removes the last of the starch.
8. Bottle, cool to room temperature, and refrigerate.

The syrup thickens as it cools. Straight from the fridge it should pour like maple syrup. If it sets like jam, you simmered it too long; stir in a splash of hot water and it will loosen.

Six drinks it works in

Use 15 ml (about one tablespoon, or one pump on a standard syrup pump) per 240 ml drink as a starting point.

• Iced banana latte. Double espresso, 15 ml syrup, 180 ml cold milk, over ice. Stir the syrup into the espresso first so it does not sink.
• Hot banana latte. Same recipe with steamed milk. A pinch of cinnamon on top turns it into a banana bread latte.
• Banana cold brew. 120 ml cold brew concentrate, 120 ml water or milk, 20 ml syrup. The syrup softens the bitterness of a strong concentrate.
• Banana cold foam. Froth 60 ml cold milk with 10 ml syrup for 20 seconds and float it on black cold brew. Oat milk foams best cold.
• Banana espresso tonic. 25 ml syrup, a double espresso and 150 ml tonic water over ice. Sounds odd, tastes like a dessert.
• Banana oat milkshake, no coffee. Blend 200 ml oat milk, 20 ml syrup and a handful of ice for the person at the table who does not drink coffee.

Getting it clear instead of cloudy

Cloudiness is banana starch and pectin, and it is harmless. If you only drink the syrup in milk drinks you will never notice it. If you want a clear syrup for tonics and cold brew, three things help: use a banana that is ripe but not mushy, never press the pulp through the sieve, and do the second pass through a paper filter. Chilling the syrup before the paper filter also helps, because the starch clumps and stays behind.

Cost per batch

A batch uses one banana, a cup of sugar and a cup of water, which comes to well under a dollar in most places. At 15 ml a pump that is about four cents a drink. A café typically charges between fifty cents and a dollar for a flavour shot, so a daily banana latte at home saves roughly $150 to $350 a year on the syrup alone. Put your own numbers into the cost per cup calculator to see the full picture with beans and milk included, and use the caffeine calculator if two of these a day is starting to look tempting.

Storage and safety

Keep the syrup in the fridge in a bottle with a proper lid. It is good for two weeks. Signs it has turned: a fizzy or yeasty smell, bubbles rising when the bottle stands still, or a film on top. Discard it if you see any of those. Sterilising the bottle with boiling water before filling and always using a clean spoon extends the life noticeably.

A tablespoon of vodka stirred in after straining acts as a preservative and stretches the syrup to about a month. At one pump per drink the alcohol is negligible, but leave it out if you are making the syrup for children.

Variations

• Brown butter banana. Melt 20 g butter in the pan until it smells nutty, then add the banana, sugar and water. Skim the foam when you strain. Richer, and excellent hot.
• Caramelised banana. Swap 50 g of the white sugar for dark brown sugar and simmer for 12 minutes. Darker colour, deeper flavour, closer to banoffee.
• Banana cinnamon. Add a cinnamon stick to the pan and remove it when you strain. This is the autumn version, and it pairs well with the maple oat latte if you want a two-syrup drink.
• Sugar-free. Allulose works at the same weight and does not crystallise. Erythritol works but can recrystallise in the fridge; warm the bottle in hot water before use. Neither version keeps as long, so make half batches.

Troubleshooting

• Cloudy: strain again through a paper filter, or accept it. It tastes identical.
• Too thick: simmered too long. Add hot water a tablespoon at a time and stir.
• Too thin: simmered too briefly, or the banana was under-ripe. Return it to the pan for three more minutes.
• Tastes cooked rather than fresh: the heat was too high. Next time keep it at a bare simmer and pull it early.
• Fermenting smell after a week: discard. Sterilise the bottle next time and keep the syrup cold.

Once you have made this once you will find yourself using the same one-banana-one-cup-one-cup method for other fruit. Strawberry, peach and pear all work with the same ratios, though each keeps for a slightly different time. More syrup and drink recipes are in Drinks & Syrups.