Ingredients

1 tbsp plus 1 and 1/4 tsp yellow mustard seeds

1 and 1/2 tsp brown mustard seeds

2 tbsp plus 2 tsp apple cider vinegar

2 tbsp plus 2 tsp water

2 tsp rosemary

1/4 tsp grapefruit zest

1/2 tsp grapefruit juice

1/2 tsp dark brown sugar

1/4 tsp sea salt

(1) 4 oz. canning jar, sterilized
Find more inspiration on http://www.adventures-in-cooking.com/2013/03/mustards-rosemary-grapefruit-and-spicy.html