2 pts. blueberries
1/4 c. granulated sugar
2 tbsp. cornstarch
Rind of 1 lemon, finely grated
2 tbsp. lemon juice
1 c. sifted flour
1/2 c. light brown sugar
1/3 c. quick-cook oats
Pinch of salt
7 tbsp. unsalted butter
1/2 c. walnuts, chopped

Butter a 6-8 cup casserole dish and preheat oven to 400 degrees. Wash blueberries. Pat dry and mix well with granulated sugar, cornstarch, grated lemon rind and juice. Spoon into prepared dish.

Mix flour, light brown sugar, oats and salt. Cut butter into small pieces and cut into flour mixture as if making pastry. Blend until crumbly and mix in chopped walnuts.

Sprinkle half of this streusel topping evenly over blueberries and cook for 10 minutes. Add rest of topping evenly and cook for another 10 to 15 minutes, until top is crisp and brown and juices start to bubble up.