For the apple mixture: In a food processor, add 4 dates, lemon juice, cinnamon and sea salt and blend until smooth. Add apples and pulse chop until apples are in tiny pieces. Remove from food processor and add to small bowls. Top with crumble topping or use as pie filling. For the crumble topping: Combine buckwheat groats and walnuts in a food processor and blend until fine. Add the remaining 4 dates, cinnamon and sea salt and process mixture until crumbly. Press into pie plate or sprinkle on apple mixture.