Recipe(tried): Date Squares (Traditional Canadian Dessert) good replacement?

This is the lightened version of the recipe. I do have my Grandmother's recipe (from someone's memory) but I haven't tried that one. If you want it too, let me know and I will post it as well. These taste exactly the same. These are just skimpy on the base and topping.

DATE SQUARES

Base
1 cup flour
1 cup oatmeal
2/3 cup brown sugar
1/4 tsp. baking soda
1/4 tsp. salt
1/3 cup margarine or butter melted

Filling
1/2 pound pitted dates chopped (2 cups)
1/3 cup brown sugar
1 cup water
1 tbsp. lemon juice

In large bowl, combine flour, oatmeal, borwn sugar, baking soda, and salt. Add margarine or butter and stir until well combined. Press half the crumbs into an 8 X 8 pan that has been sprayed with no stick spray.

Combine dates, brown sugar and water in a small saucepan over medium heat. Bring to a simmer and cook, stirring often for 5 to 10 minutes or until thick. Remove from heat and stir in lemon juice.

Spread filling over crust and sprinkle with remaining crumbs. bake for 30-35 minutes at 350 degrees until golden around the edges. Cool in the pan on a wire rack.

Makes 16 squares.

If you want an unlightened version - I would just try doubling the base mixture.