Step 1

To begin, combine the diced onions and butter in a heavy Dutch oven.

Step 2

Cook over low heat for 1-3 hours, low and slow until the onions are very soft and golden. Stir frequently to prevent scorching. The onions will reduce in volume considerably.

Step 3

Once the onions are ready, add the remaining ingredients.

Step 4

Increase the heat to a very gentle simmer and cook until it has reduced to a nice, thick jam consistency.

Step 5

Ladle the hot jam into hot, 4 ounce canning jars. Allow for 1/4 inch of head space.

Step 6

Remove air pockets with a bubble wand, and wipe the rims of the jar with a damp cloth that is dipped in white vinegar.

Step 7

Place a lid and ring on the jar and place it in the canner. Repeat with all the jam.

Step 8

Process the jars for 10 minutes in a hot water bath or steam canner. Adjusting for elevation if needed. (See note in the article above.)

Step 9

When the jars have processed, transfer them to a lined surface in a draft free location. Cool for 12-24 hours.

Step 10

Remove the rings, test the seals and label the jars. Store in your pantry for up to a year. If any jars didn't seal, put them in the fridge to use right away.

Step 11

Enjoy!