Onion Sauce

2 medium onions, thinly sliced
1 cup no-salt-added tomato sauce
1 Tbsp. apple cider vinegar
Garlic powder and black pepper to taste

Place all ingredients in small saucepan. Bring to a boil, and
then reduce to simmer.

Cook until onions are soft and sauce has thickened and becomes

Use as a burger topping.