In a medium saucepan, heat oil over medium-high heat. Add the onions and cook, stirring, until soft and slightly caramelized, 4 minutes. Add the garlic to the pan and saute for 1 minute. Add the chipotle chiles and cook, stirring continuously, for 1 minute. Add the raspberries and cook until soft, 2 to 3 minutes. Add the vinegar and stir to deglaze the pan. Add the sugar and salt, and bring to a boil. Reduce the heat to medium and simmer until thickened and reduced by half, 8 to 10 minutes. Remove from the heat and cool before using.For a clear glaze, strain through a fine mesh strainer, pressing on the solids with the back of a spoon to extract as much liquid as possible.Serving Suggestions:Use as a barbecue sauce, glaze, or basting sauce for poultry, shrimp, and meats. Pour over a block of cream cheese and serve as a dip with club crackers. Use as a sauce for meatballs or cocktail sausages for a crowd-pleasing appetizer. Great in wraps.Yield: about 1-1/2 cups