Peel and mash the ripe bananas in a pan.

Add the brown sugar, water, cinnamon, and nutmeg.

Heat the pan until it comes to a boil, then reduce to a gentle simmer.

Simmer for about 10 minutes.

Let the mixture cool, then blend until smooth.

Transfer the syrup to a sterile jar or a drink syrup bottle.

Use it to flavor lattes, matcha, or other drinks.