In a large bowl, combine the olive oil, maple syrup, balsamic vinegar, wholegrain mustard, garlic powder, rosemary, salt and pepper.
1 tablespoon olive oil, 2 tablespoons maple syrup, 2 tablespoons balsamic vinegar, 2 teaspoons wholegrain mustard, ½ teaspoon garlic powder, ½ teaspoon finely chopped fresh rosemary, ½ teaspoon sea salt, ¼ teaspoon freshly ground black pepper