Apple Oat Walnut Squares

Ingredients:
- 2 cups oats
- 1 cup flour
- 1 cup brown sugar
- 1/2 teaspoon salt
- 1/2 teaspoon baking soda
- 1 tsp cinnamon (if using apples)
- 1 cup chopped walnuts
- 3/4 cup butter or margarine, softened
- 3 cups diced fresh apples (about 4 apples)- may also substitute 3 cups frozen blueberries
- 1/2 cup sugar
- 1/3 cup orange juice
- 4 teaspoons cornstarch
Directions:
1. Filling: In large saucepan, bring apples (or berries), sugar and orange juice to boil. Reduce heat and simmer until tender, about 10 minutes. Whisk in cornstarch and boil until thickened, about 1 minute. Cool for about 1 hour or overnight before using.
2. Base/topping: In a large bowl, stir together the oats, flour, brown sugar, baking soda, salt and cinnamon (if using apples). Cut in butter to form a crumbly mixture. Reserve 1 1/2 cups of the crumbs and pat the rest evenly into the bottom of a greased 9 x 13 inch pan.
3. Spread the apple or berry mixture over the base. Crumble the reserved base/topping over the mixture.
4. Bake at 350 degrees F until golden, about 40-45 minutes. Let cool completely on rack as they cut better when fully set and cooled. To make- ahead, cover and refrigerate for up to 2 days or over wrap with heavy duty foil and freeze for up to 2 weeks. Cut into bars, serve, or store in airtight containers and freeze if desired.