Add dried mustard, beer and vinegar to a medium pot over medium heat. Stir to combine everything.
Cook for 2 minutes.
Stir continuously while adding the brown sugar, honey, Worcestershire sauce and salt. You want to use the heat at this point to melt the brown sugar and incorporate the salt fully into the mustard mixture.
Once everything seems fully combined, remove from the heat and whisk in your 2 tablespoons of oil.
Allow mustard to cool and then add to a container or jar.
At this point you can taste it if you want, but it will be quite bitter. It takes 3 or 4 days to fully mellow the flavor and for all of the mustard powder to bloom in the condiment.
Store hot mustard in the refrigerator for up to 3 months.