Microwave Berry Crumble

Name: Microwave Berry Crumble
Prep time: 5 min
Cook time: 3 min
Total time: 8 min
Cuisine: British
Ingredients: 1 tbsp butter or coconut oil (softened ); 1/2 tbsp maple syrup or sugar; 2 tbsp oats (quick, minute or rolled); 2 tbsp oat flour ((all-purpose flour also works)); 1 tsp cinnamon; 1 cup berries of choice (frozen or fresh ); 1/4 cup walnuts (chopped (optional)); 1/2 tbsp butter or coconut oil (softened); 1/2 tbsp maple syrup, honey or sugar; 1/2 tsp cinnamon; sprinkle of ground ginger; 1 tsp cornstarch