This lemon blueberry crumb cake recipe is a perfect combination of sweet and tangy flavors. The cake is made with flour, sugar, baking powder, salt, butter, eggs, milk, lemon zest, and fresh blueberries. The lemon zest adds a refreshing citrus flavor to the cake, which complements the blueberries perfectly. To make the cake, mix the dry ingredients, cream the butter and sugar, add the eggs and lemon zest, and alternate adding the dry ingredients and milk. Fold in the blueberries and pour the batter into a greased baking dish. For the crumb topping, mix flour, sugar, and butter until crumbly, and sprinkle over the cake batter. Bake for 45-50 minutes, and enjoy a delicious lemon blueberry dessert!