3 cooked bacon slices, crumbled
2 garlic cloves, minced
1 cup orange zest
1/2 cup loosely packed fresh flat-leaf parsley leaves, finely chopped
1 tbsp. cold water
2 tsp. cornstarch
2 tsp. chopped fresh rosemary
2 tsp. kosher salt
3 tbsp. light brown sugar
4 tbsp. butter, melted
1/2 cup frozen orange juice concentrate, thawed
4 pounds slender sweet potatoes, peeled and cut into 1-inch-thick slices