Makes about 6 cups
Make-Ahead: The sauce can be made 2 weeks ahead.
You'll find some kind of sweet onion (such as Maui, Walla Walla, or Texas Sweets) available at any time of the year, but late spring is the time for Georgia's Vidalia onions. While their inherent sweetness is a fine accent to smoky ribs, keep this sauce in mind for chicken, too. If you have leftover sauce after cooking the ribs, serve it one the side as a dip, or refrigerate it for another meal. It keeps very well.
1. To make the sauce, melt the butter in a heavy-bottomed, medium saucepan over medium-low heat. Add the onions and cover. Cook, stirring often, until the onions are golden brown, about 15 minutes. Add the garlic and cook, uncovered, until it gives off its fragrance, about 2 minutes. Stir in the peach fruit spread, chili sauce, mustard, molasses, vinegar, and Worcestershire sauce. Bring to a simmer, stirring often. Reduce the heat to low and simmer, stirring often to avoid scorching, until lightly thickened, about 30 minutes. (The sauce can be prepared up to 2 weeks ahead, cooled, covered, and refrigerated.)