Preheat oven to 350 degrees Fahrenheit and grease a glass baking dish (I use a rectangle 8" x 11" dish but anything close in size to this will work).
*Sift the tigernut flour before measuring if desired (see notes).
In a medium bowl, mix the dry ingredients.
In another medium bowl mix wet ingredients.
Mix the dry ingredients into the wet ingredients and stir until smooth.
Pour the batter into a greased glass baking dish and place in the oven- (it will bake for 30 minutes and then be taken out for a moment to add the crumb topping).
Make the crumb topping- combine the crumb topping ingredients in a small bowl. Mix by hand and try to keep some of the clumps intact.
After 30 minutes of baking, remove the cake from the oven add the crumb topping, distributing it evenly across the top. Return it to the oven to bake for an additional 20-25 minutes or until a toothpick comes out clean.
In a small bowl, mix the cinnamon dusting sprinkle ingredients- this part is optional but adds some additional cinnamon flavor and it looks nice. Just keep it fairly light.
Once the cake has finished baking (about 50-55 minutes total), remove it from the oven and allow to cool. Sprinkle lightly with the cinnamon sprinkle dusting and serve!
Notes
*You can use a sifter or a strainer to get any little clumps out of the tigernut flour. This is optional but produces a better end product. However, it should be noted that sifting will change the measurements slightly. If you don’t sift the flour, you’ll need 1 ½ cups. If you do sift it, you’ll need 1 ¾ cups. This will stay fresh in the fridge for 3-4 days in a tightly sealed container or up to 3 months in the freezer.