Prepare Blueberries: Wash and dry 4 cups of blueberries. Combine with 1/2 cup sugar, 1/2 cup water, and cinnamon in a Dutch oven. Place over medium heat and simmer for about 5 minutes.

Stew Blueberries: Cook for 5-10 minutes, stirring occasionally, until juices thicken slightly.

Make Dumpling Dough: In a bowl, sift together 2 cups flour, 1 tablespoon baking powder, and 1/4 teaspoon salt. Cut in 6 tablespoons cold butter until coarse crumbs form. Gradually add 3/4 cup cold milk, stirring until a sticky dough forms.

Add Dumplings: Drop spoonfuls of dumpling dough onto the simmering blueberries, spaced evenly.

Cook Dumplings: Cover tightly and steam over low heat for 15 minutes without lifting the lid.

Serve: Gently scoop into bowls while warm, serve with vanilla ice cream or whipped cream.