For blueberry sauce: In a 2-quart saucepan, mix together sugar, cinnamon, nutmeg, and cornstarch. Stir in water and lemon juice. Heat to boiling; reduce heat. Set aside about ¾ cup of the blueberries for the waffles and stir in the remaining blueberries into sauce. Simmer for 5 minutes. Remove from heat, cover, and set aside to keep warm while preparing waffles.
For blueberry waffles: Heat waffle iron. In a bowl, beat eggs, then remaining ingredients until smooth. Pour batter into center of hot waffle iron. Scatter with a few tablespoons of the reserved blueberries for each batch of waffles. Bake until the steaming stops and waffles are a golden color, about 4 minutes. Remove waffles carefully. Serve squares (or rounds) with warm blueberry sauce and serve.
Recipe by The Culinary Cellar at https://theculinarycellar.com/sphere-magazine-august-1973/