Cowboy Baked Beans and Sausage

16 oz smoked sausage link or kielbasa
1 1/2 C. coarsely chopped onions
3/4 C. bottled barbecue sauce
2 Tbsp. pancake syrup
1 Tbsp. cider vinegar
1 (15 oz) can red kidney beans, drained
1 (15 oz) can pinto beans, drained
1 (15 oz) can black beans, drained
Sliced green onions (garnish)

Heat a large skillet over medium - high heat. Add sausage; cook, turning slices once, 3 minutes or until browned. Remove to a bowl. Add onions to drippings in skillet. Cover and cook 8 minutes stirring occasionally until tender and golden. Add barbecue sauce, syrup and vinegar; bring to a boil. Stir in beans and sausage. Heat, covered, over medium heat 15 minutes, stirring often for flavors to blend. Sprinkle with green onions if desired.