How to substitute for mustard seed<br>Use prepared horseradish to add spice. Prepared horseradish is made by combining ground horseradish with vinegar, and sometimes other spices, to form a sauce. You can get it from your local supermarket.
Making horseradish from scratch is easy.
( z1 make :ARG1 ( z2 horseradish ) :manner ( z3 scratch ) :ARG1-of ( z4 easy ) )