In a large bowl, whisk together flour, sugar and baking powder. Cut butter into small pieces. Add egg, milk, butter and lemon peel; mix just until dry ingredients are moistened.
1
Fold in the blueberries. Because the batter is so thick, this may take a few minutes. Spread into a greased 9-in. square baking pan.
2
For topping, combine sugar, flour, walnuts and cinnamon in a mini food processor or bowl. Add butter and process, or cut in if doing by hand, until mixture is crumbly.
3
Make sure you are measuring your flour properly. Always measure flour using the “scoop and sweep” method.
TIPS