A St. Patrick's Day spicy Guinness mustard

In honor of St. Patrick's Day, I wanted to make spicy Guinness mustard. I'd first seen the recipe months ago on a great food/photography blog, Chasing Some Blue Sky. As it was during my Summer of Living Kitchenlessly, I made a mental note and stashed it away in my cluttered brain.

Fast forward to last night when I finally sat down to make a grocery list. (I'd meant to make the  mustard earlier this week, but somehow, volunteering at the kids' schools devoured my schedule. Like a 50s horror flick..The PTO of Terror! (In 3D!). Don't get me wrong. I love working at the schools. I love getting to know the kids and chatting with parents. But sometimes, I really need to exercise my "saying no" skills.) Anyway, last night I discovered that...oops...the ingredients are supposed to sit for 1-2 days. And I don't have 1 1/2 cups of brown mustard seeds at hand. Soooo...

Here's the mustard-to-be, steeping away. I'll let you know how it tastes in a couple of days. (I'm planning to have it with Irish bangers...and maybe more Guinness.)

Spicy Guinness Mustard
From Saveur Issue 117

1 12-oz. bottle Guinness Extra Stout
1 1⁄2 cups brown mustard seeds (10 oz.)*
1 cup red wine vinegar
1 tbsp. kosher salt
1 tsp. freshly ground black pepper
1⁄4 tsp. ground cinnamon
1⁄4 tsp. ground cloves
1⁄4 tsp. ground nutmeg
1⁄4 tsp. ground allspice

Combine ingredients in a nonreactive mixing bowl. Cover with plastic wrap and let sit at room temperature for 1–2 days so that the mustard seeds soften and the flavors meld.

Transfer the mixture to the bowl of a food processor and process, stopping occasionally to scrape down the sides of the bowl with a rubber spatula, until the seeds are coarsely ground and the mixture thickens, about 3 minutes. Transfer to a jar and cover.

Refrigerate overnight and use immediately or refrigerate for up to 6 months. (The flavor of the mustard will mellow as the condiment ages.)

*I found brown mustard seeds in the Indian food section of the grocery store. Just a suggestion if it's not stocked with spices.

Note: Here's the followup to my spicy Guinness mustard.