Combine the blackberries, sugar, water, butter, and cinnamon in a large pot. Cook over medium-low heat for 20 to 30 minutes, stirring occasionally until the berries break down into a thick sauce.

In another bowl, whisk together the flour and salt. Cut in the shortening until the mixture resembles coarse crumbs.

Stir in the egg yolk, and gradually add milk, one tablespoon at a time, until the dough forms a ball.

Divide the dough in half and roll each half on a floured surface to 1/4 inch thickness. Cut strips 2 to 3 inches wide.

When the berry mixture is bubbling, pinch off pieces of dough (about 4 inches long) and drop them into the bubbling sauce.

Reduce heat to medium and let the dumplings cook for 15 minutes without stirring. Push them down gently if they float.

Remove from heat and let rest for 10 minutes to thicken before serving.

Serve Blackberry Dumplings in bowls, optionally topped with evaporated milk or ice cream.