What fruits does he like? Maybe make an fermented apple chutney? Or pear or cranberry?
Maybe serve it in a way so he does not think it is a pickle?
I am thinking of a Christmas like salad, etc. Just can not think of the name.
Here is something that I found:
Ingredients
24 ounces fresh organic cranberries
2 large apples
Zest from 1 orange
1/2 vanilla bean, split
1 tablespoon whole cloves
2 cinnamon sticks
3 tablespoons minced fresh ginger
1 1/2 cup raw honey
1/2 cup organic whey, preferably from raw yogurt, kefir, or clabber milk (see note)
Filtered water to cover
After the ferment has finished:
4 tablespoons gelatin
1/4 cup filtered water
https://www.butterforall.com/traditional-cooking-traditional-living/lacto-fermented-cranberry-salad/