Start by trimming any discolored or bruised sections of the mushrooms. Trim stems to remove bruising at the bottom. Then place the mushrooms in a large bowl and let them soak in cold water for at least 10 minutes to remove the dirt. You can use this time to prepare your jars and begin to heat up the water in a large stockpot.

Rinse the mushrooms after the soak.

If you have small mushrooms, you can leave them whole or cut them in half. The mushrooms I canned were large, so I sliced them first. Since this is also how we will use them later, that made the most sense to me.

Place all the mushrooms into the boiling pot of boiling water and let them boil for 5 minutes. You want just to get them heated through for canning; you don't need to cook them.

Strain the mushrooms in a colander. Place a kettle, saucepan, or a large pot filled with clean water on the stove to boil. You will fill the jars with fresh hot water and not the water they heated up in.

Place the mushrooms packed tightly into half-pints or pint-sized jars. You can add 1/4 teaspoon of salt to half pints or double that for pints if you'd like. I choose not to add salt to my canned foods. You can add 1/8 teaspoon of ascorbic acid powder or a 500-milligram vitamin C tablet for better color to each pint jar. (Half the amount for half-pint jars.) The discoloration doesn't bother me, so we chose not to do this.

Fill the jars with the boiling water from the kettle, leaving 1-inch headspace.

Use the bubble remover to eliminate any air bubbles in the jars.

Wipe jar rims with a clean wet cloth to remove residue and place the lids and rims on the jars. Do not overtighten the lids! Fingertip tightness is perfect.

Once the pressure has gone back down, you can remove the lid of the canner and remove the jars using a jar lifter. I always place them on a cloth on a cutting board so that the heat from the jars doesn't ruin my countertops.

Let the jars cool undisturbed until they are sealed. After sitting for about 24 hours, you can remove the rims and put the jars in your pantry.