סימן פ סעיף כ
אִם צָרִיךְ לָדוּךְ פִּלְפְּלִין אוֹ מֶלַח וְכַיּוֹצֵא בוֹ לָתֵת לְתוֹךְ הַמַּאֲכָל, מֻתָּר לָדוּךְ בְּקַתָּא דְּסַכִּינָא עַל הַשֻּׁלְחָן וְכַיּוֹצֵא בּוֹ, אֲבָל לֹא בִּמְדוּכָה וְלֹא בְּמַכְתֶּשֶׁת.
If you must crush pepper or salt,87The Kitzur Shulchan Aruch and Mishnah Berurah 321: 28 compare salt to pepper and rule that it must be crushed in a very irregular way with two deviations from the normal procedure. and similar items, to put into food, you may crush (them) with the handle of a knife on the table,88Two deviations: Handle instead of pestle, and tabletop (or plate) instead of mortar. Pressing garlic should be done with two deviations, if possible. See Shulchan Aruch Harav and Minchas Shabbos. or with similar methods. But not with a mortar and pestle,89It is also forbidden to cut them very fine with a knife (blade). If you want to cut them (peppers, spices) to put in the food for immediate use, it is permitted. (Shaar Hatziyun—Mogen Avraham and Vilna Gaon [and Kilkeles Shabbos]) or with a hand-mill.90Salt or sugar that was pre-cooked and is considered pre-ground may be crumbled by hand if they get lumpy because of humidity. See Shaarei Teshuvah 328: 30 and Rema 321: 8 and Mishnah Berurah 321: 29—Shibolei Haleket.
תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן העולם הבא שנאמר הליכות עולם לו אל תקרי הליכות אלא הלכות (נדה ע"ג.)