Preheat oven to 350°.
Butter an 8-inch square glass baking dish. In a medium bowl, combine ⅓ cup flour, ½ cup sugar, and cinnamon. Using your fingers, rub in butter until mixture is crumbly.
In a small bowl, whisk remaining 1 cup of flour with baking powder and salt. In a large bowl, using a handheld mixer, beat remaining ½ cup of sugar with shortening. Beat in the egg. Beat in flour mixture in two batches, alternating with milk.
Spread batter in the prepared baking dish. Scatter blueberries over the batter. Sprinkle with cinnamon crumble topping and bake for 40 minutes. Let cool slightly.
Serve warm or at room temperature, with whipped cream if desired.
Enjoy!