Step 1

Cut asparagus spears into 1-inch pieces.

Step 2

In a large stockpot, melt the butter.

Step 3

Add onion and sauté until translucent.

Step 4

Add asparagus, salt, and pepper, and cook, stirring frequently, for 8-10 minutes until asparagus begins to soften.

Step 5

Add garlic, stir, and cook one minute more.

Step 6

Add chicken broth and bring the soup to a boil.

Step 7

Once the soup boils, reduce to a simmer and cook for half an hour.

Step 8

Blend soup with an immersion blender (or carefully in batches in a blender) until completely smooth.

Step 9

Add optional toppings and serve immediately.

Step 10

Prepare your jars, lids, rings, and canner.

Step 11

Wash your jars, lids, and rings in hot, soapy water.

Step 12

Fill the pressure canner with 2-3 inches of water and put it on the stove on a low heat to warm.

Step 13

Put a little water in the clean jars to keep them weighed down, and place them in the canner.

Step 14

Turn the canner off when it begins to steam to keep the jars warm.

Step 15

Fill jars, fit lids, and place in pressure canner.

Step 16

Remove the hot jars from the canner and turn the canner on again to bring the water to a low simmer (180°F).

Step 17

Use a funnel to fill the jars with asparagus soup, leaving 1 inch of headspace. Release the bubbles, adding more liquid if needed.

Step 18

Clean the rims of the jars with a vinegar-soaked towel and gently screw on the lids to fingertip tight.

Step 19

Carefully place the jars into the pressure canner.

Step 20

Place the lid on the pressure canner and turn up the heat.

Step 21

Let the steam vent for 10 minutes.

Step 22

Put the pressure regulator on the lid.

Step 23

Bring the canner to 11 PSI on a dial gauge or 10 PSI for a weighted gauge (adjust for elevation).

Step 24

Once your canner has stabilized at full pressure, set a timer for 60 minutes for pint jars (75 minutes for quarts).

Step 25

Turn off the heat, then let the canner come down to 0 PSI by itself.

Step 26

Remove the pressure regulator and let the canner stabilize for 5 minutes before removing the lid.

Step 27

Carefully take the lid off the canner.

Step 28

Remove the jars and set them on a clean towel where they can cool undisturbed for 16-24 hours.

Step 29

Check each seal, remove the bands and clean jars with room-temperature water, if needed.

Step 30

Label each jar with the contents and year.

Step 31

Store the jars out of direct sunlight.