Step 1

Chop up the dried fruit and the apple. Mostarda is traditionally made from bite-sized chunks, but finely diced is also fine.

Step 2

Place the fruit in a pint-sized (2 cup) jar. Add in the mustard seeds and honey. Pour over the water. Press the fruit down in the jar. There should be enough water to cover the fruit, if not add a few more spoonfuls.

Step 3

Cap the jar with a lid that can handle the carbonation of fermentation (see notes). Place the jar in a dark location. A kitchen cupboard is perfect.

Step 4

The fruit and mustard will float, however, I’ve found a weight doesn’t help as the mustard will just escape around the sides. Instead, of using a weight, simply stir the mostarda once or twice during fermentation (after 12 or 24 hours). Let the mostarda ferment for 2 to 4 days.

Step 5

Store the mostarda in an airtight container in the fridge. It will be sparkling and sweet for the first week or so, then become more mellow and acidic over time. Enjoy within 4 to 6 weeks.