In medium size sauce pot add rinsed blueberries, 1 cup of water and sugar. Bring to boil. Lower heat, and let simmer until the blueberries start to break down.

In a cup add the flour and some cold water (approx. 1/2 a cup). Mix quickly; the mixture should look like milk. Bring blueberry mixture to a low boil and stir in slurry. The slurry will thicken the blueberry mixture. Add a dash of cinnamon, lemon zest or the jelly, if you like, to give the mixture some complexity. Remove from heat and let topping cool.

You can use this topping on pancakes, waffles or ice cream. You can also use the topping in a frozen pie crust topped with a crumble topping; bake at 350 degrees for approx. 55 minutes.