Spicy Espresso Steak Barbecue Sauce

Love the flavour of Espresso in this sauce.  Kick up the BBQ a notch and try this out on steak or chicken.

1 bottle (700 ml) strained tomatoes or passata
1 onion, finely chopped
1/2 cup brown sugar
2 tbsp espresso powder
1/4 cup tomato paste
1/4 cup Worcestershire sauce
1/4 cup cider vinegar
2 garlic cloves, minced
2 chipotles in adobo sauce, finely chopped
1 tbsp mustard powder

1. Place ingredients in a small saucepan and stir to mix.  Bring to a gentle boil over medium heat.  Simmer, stirring occasionally, until flavours infuse and sauce thickens slightly, about 20 minutes.  
2. If making ahead, cover and refrigerate until ready to use.  

Use for a marinade or to coat and bbq.  Also great on the side for dipping.