Can anyone give me some feedback on he viability of this recipe? It sounds tasty but the 1/4 cup of butter scares me. Thank you.

4 whole garlic bulbs
1 teaspoon canola oil
5 cups chopped sweet onions (1-1/2 pounds)
1/4 cup butter, cubed
3/4 cup cider vinegar
1/2 cup bottled lemon juice
1/4 cup balsamic vinegar
1-1/2 teaspoons ground mustard
1 teaspoon salt
3/4 teaspoon white pepper
1/2 teaspoon ground ginger
1/4 teaspoon ground cloves
6 cups sugar
1 pouch (3 ounces) liquid fruit pectin

Directions
Remove papery outer skin from garlic (do not peel or separate cloves). Cut top off garlic bulbs; brush with oil. Wrap each bulb in heavy-duty foil. Bake at 425� for 30-35 minutes or until softened. Cool for 10-15 minutes.
In a Dutch oven, saute onions in butter for 30-40 minutes or until lightly browned. Squeeze softened garlic into pan. Stir in the cider vinegar, lemon juice, balsamic vinegar, mustard, salt, pepper, ginger and cloves. Bring to a rolling boil. Gradually add sugar, stirring constantly. Return to a boil for 3 minutes.
Add pectin; bring to a full rolling boil. Boil for 1 minute, stirring constantly. Remove from the heat; let stand for 3 minutes. Skim off foam. Pour hot mixture into hot jars, leaving 1/4-in. headspace. Adjust caps. Process for 10 minutes in a boiling-water bath. Yield: about 3-1/2 pints.

Butter and oils can make mirco-environments in canned goods appropriate for bacteria to grow.

As we don't know where the recipe came from (i.e. the original source's credentials) the safest option is to assume it's too high a risk to can and just freeze it.

Carol