Place the butter, diced red onions, and minced garlic into a medium pot.

Cook over medium-low heat for approximately 20 minutes, until the onions are significantly reduced and caramelized.

Add the ground black pepper, salt, honey, apple cider vinegar, apple juice, and dried thyme to the pot.

Simmer on low heat, stirring frequently, for another 20 minutes or until the mixture thickens to a jam-like consistency. Ensure most of the liquid has evaporated.

Serve warm or reheat in the microwave as needed.

Store in a sealed container in the refrigerator for several days. For longer storage, follow proper canning methods as recommended by jar manufacturers.