Combine 2 cups raspberries and 1/4 cup maple syrup in an upright blender and blend until smooth. (golubkakitchen.com)
I would begin by substituting only 1/2 cup maple syrup for part of the corn syrup in the whole recipe (or 1/4 cup for the half recipe). (kingarthurflour.com)
I didn't add the blueberries (I didn't have any) and I used 1/4 cup maple syrup instead of the 1/2 cup agave nectar. (blog.fatfreevegan.com)