Add lemon zest & juice to blueberries.
Mix with cornstarch and sugar.
Add to ovenproof ceramic dish.
Mix dry ingredients with sugar, add butter and integrate with your hands or pastry cutter.
The butter should be the size of peas.
Add milk until you have a soft, moist dough.
Spoon over the blueberries and bake for 40-45 minutes or until golden.
Enjoy warm or at room temperature.