Ready in 7 hours
Our friend Mindy makes this dip and it is delicious. WARNING: it's a very spicy mustard dip, but it's a really good flavor. Ask anyone what they think is in it and most will guess it's horseradish...but it's not. The secret is Colman's mustard!
Mix mustard and vinegar in bowl and soak overnight. Add remaining ingredients, except sour cream. Cook on medium heat until “custardy”. Let cool, then add sour cream. Serve with sour dough pretzels (soft or hard). Be sure to warn your guests that it's spicy!