Preheat oven to 200 Degree C.
Take dates, sugar and water in a sauce pan and bring it to a boil. Cook till it thickens. Set aside to cool.
Take butter, brown sugar and vanilla and mix well.
Add in flour, baking soda, salt. Mix well.
Add in oatmeal and mix well till it forms crumble.
Spoon half of the mixture, in the pan and press firmly using a cup.
Spoon dates filling in and top with more crumble and press gently.
Bake for 35 to 40 mins.
Cool it completely.
Slice into bars and serve.