In a large pot, combine blueberries, 1 and ½ cup sugar, and 2 cups of water. Bring to a low boil.
For the dumplings
While the sauce is coming to a boil, mix the dumplings.
In a medium bowl, stir flour, 2 tablespoon sugar, baking powder, salt, and lemon zest together.
Cut the butter into the dry ingredients with a pastry blender or fork. When the mixture resembles wet sand, stir in the milk to form a dough.
Cook the dumplings
With the sauce at a low boil, drop ½ tablespoon dough into the sauce working as quickly as you can.
Cover the pot and reduce the heat to low or simmer. Cook on low for 20 minutes (more if needed). Don't remove the lid and do not stir until 20 minutes. Check the dumplings at 20 minutes for doneness. The dumplings should be fluffy and cooked through with no doughy centers when done.
Gently stir in the lemon juice. Serve warm with vanilla ice cream and/or fresh whipped cream.