Coarsely crush the Nilla Wafers and zest the lemon. Squeeze 1 Tbsp. Joice from the lemon. In a blender, blueberries, nil, lemon zest, brown sugar, lemon juice and crushed wafers. Blend until wafers break down. Add the ice cream and blend until smooth. Divide between four glasses. Optional: top with whipped cream, extra cookies and fresh blueberries.