Place the bacon in a cold pan or Dutch Oven. Turn the heat to medium and cook until the bacon is crispy. Remove with a slotted spoon and drain on a paper towel-lined plate.

Add the onion and cabbage to the bacon grease, and cook, stirring, until the cabbage just begins to wilt, about 10 minutes. Add the vinegar, maple syrup, and tamari. Reduce the heat, cover the pot, and simmer, stirring frequently, until the cabbage is tender but not mushy, about 20 – 30 minutes. Stir in the bacon and serve.