I like mustard of any variety. On burgers, sandwiches, Welsh rarebit, vinegar and mustard BBQ sauce, it's all good stuff.
Dad always had a jar of Mister Mustard in the fridge. Haven't seen that brand in a while, but it was good stuff on a slice of cheddar cheese.
My mustard steak recipe-
A big hunk of top round, flank, or tritip. Slather in yellow mustard until completely covered. Place on a bed of coarse kosher salt on a large plate or cutting board and completely cover in the coarse salt.
Get a good bed of charcoal ready and place the salt covered steak directly on the coals. Cook to med-rare.