For the chow-chow: Combine the cabbage, salt, onions, bell peppers and tomatoes in a medium bowl. Refrigerator overnight or set aside on the counter for 2 hours.
Rinse the vegetables thoroughly in a colander and set aside. Combine the vinegar, sugar, mustard seeds, coriander seeds, turmeric, red pepper flakes, ginger and garlic in a saucepot with 1/2 cup water and bring to a boil over medium-high heat. Simmer for 5 minutes, and then add the vegetables and simmer until softened, 5 minutes more. Cool and refrigerate until ready to use.
For the burgers: Place the bacon in a large skillet over medium heat and cook until browned and crisp, turning occasionally, about 12 minutes. Transfer to a paper-towel-lined plate to drain, and then chop each strip in half crosswise. Reserve 1 teaspoon of the rendered bacon fat and stir into the mayonnaise.
Preheat a grill to medium-high heat. Divide the ground beef into four 6-ounce patties, 4 inches wide and 1-inch thick. Brush the burgers with the oil and sprinkle both sides with salt and black pepper. Grill the burgers until the meat is visibly cooked more than halfway up the side, about 4 minutes, and then flip and cook until medium rare, 4 minutes longer. Remove from the heat and let rest for 5 minutes.
Spread 1 tablespoon of the mayonnaise on the bottom of each bun, then add the burgers, bacon and 1/4 cup chow-chow to each. Serve.
Save any remaining chow-chow in the refrigerator for up to 7 to 10 days.