Place a 12-cup or two 6-cup muffin tins in oven and preheat oven to 425° (with muffin tins in oven).
Mix up the lemon sugar by stirring together the white sugar and lemon zest in a small bowl. Set aside.
Make the Dutch baby batter by combining all the pancake ingredients in a blender and mixing well, until frothy. Leave in blender.
When oven is preheated, melt additional 2 Tbsp butter. Remove hot muffin tins from oven and quickly brush bottoms and sides of pan with melted butter. Turn blender on for a few seconds to re-mix batter, then quickly pour in to hot muffin cups, dividing equally between 12 cups, filling about 1/2 full.
Place in oven and bake for 15-18 minutes, or until puffy and deep golden colour.
While Dutch Babies are baking, made blueberry sauce. Add blueberries to a 2-cup or larger microwaveable measuring cup or bowl. Add remaining sauce ingredients and stir to combine. Microwave on high for 1 minutes. Stir. Microwave for 1 more minute, or until blueberries are softened and sauce is thickened. (Sauce will thicken a bit further as it sits). *If starting with frozen blueberries, you may need another 30 seconds or so. Serve warm, re-warming a bit, if necessary. (*You can also make the sauce in a small saucepan on the stove-top. Simply bring mixture to a boil, stirring, then allow to simmer for a few minutes).
Remove from oven (pancakes will quickly deflate). Immediately sprinkle with lemon sugar while still warm. Remove pancakes to serving plates and spoon warm blueberry sauce over. Enjoy warm, fresh from the oven with a garnish of icing sugar.
Be sure to read the "Cook's Notes" in the original post, for more tips, options, substitutions and variations for this recipe!