For button and cremini mushrooms, choose slices for a sauté or halves and quarters for recipes that need larger pieces. Portobello caps can be cut into thick strips for baked mushroom fries. Briefly rinse or wipe away dirt, pat dry, and make a flat base before slicing a mushroom that rocks.
Clean, trim, and steady the mushroom
For familiar mushrooms sold as food, brush away loose dirt or briefly rinse under running water and pat dry. Do not use soap or produce wash. Trim only a dry or tough stem end; firm button and cremini stems can stay attached. Set a clean board on a steady counter and curl your guiding fingertips back as you cut.
Slice or quarter button and cremini mushrooms
For slices, set a small cap stem-side down. Hold it with curled fingertips and cut straight down through cap and stem. If it rolls, cut it in half through the stem, put each half cut-side down, and slice across it.
For quarters, halve the mushroom lengthwise through cap and stem. Put each half cut-side down, then cut across its middle to make four pieces. This gives a recipe that calls for quarters a stable, repeatable cut; follow its requested size when the mushrooms are unusually small or large.
Prepare a portobello cap
If the stem is tough, twist it free or cut it away at the base; keep it only if your recipe will use it. Portobello gills can stay or be scraped out with a spoon according to preference. Removing them is optional, not a cleaning step.
For strips, remove a protruding stem so the cap can rest gill-side down on the board, then cut parallel slices across it. If the cap still rocks, halve it through the center, place the flat cut face down, and slice each half. Colorado State University Extension’s baked portobello fries use thick slices; follow your own recipe’s requested size.
For a refresher on board setup and basic knife control, see our beginner knife-skills guide.
Sources: U.S. Food and Drug Administration, “7 Tips for Cleaning Fruits, Vegetables” (rinse under running water, no soap or produce wash, dry); Mushroom Council, “How-to: Select, Store and Clean Mushrooms” (wipe or briefly rinse, pat dry, trim tough stems, gills by preference); Utah State University Extension, “Fruit and Vegetable Guide Series: Mushrooms” and “Green Bean Mushroom Medley” (slices for sautéing); Milk Street recipe reported by the Associated Press, “Tomato-Mushroom Curry” (halved medium or quartered large caps); Colorado State University Extension, “Baked Portabella Mushroom Fries” (thickly sliced caps).