The miso-honey mustard can be refrigerated for up to 1 week. Bring to room temperature before using.
White miso (also called shiro miso) is made from fermented soy beans and rice. It's not fermented for long, so the flavor is quite mild. It's the most versatile of misos. Look for it at large supermarkets.
Grilled chicken or pork, as well as vegetables like cabbage and turnips.