Ha, I made my own mustard! My fiancée was disappointed we had no mustard in the fridge at ALL, and specifically was dreaming of spicy mustard.
Spicy mustard you ask for, spicy mustard you shall have!
How hard could it be?
Brand new mortar and pestle from Ikea, mustard seeds I had left over from a chutney recipe, apple cider vinegar, olive oil, salt and ground mustard.
I will leave out a decided recipe here because I think it needs work, but essentially, it was simple: crush up mustard seeds, add oil and vinegar and mustard powder and mix around. Mustard is an emulsifier between oil and water, it is often added to salad dressings for that reason... so it turned into a paste like...mustard. Weird and fun.
He liked it- it did start off a sneezing watery-eye "wasabi-like" reaction. Ill tweak the homemade mustard and get back to you.