Vegan Blueberry Streusel Coffee Cake

I found a recipe for a blueberry streusel cake in a vegan cookbook. But I didn't like the extra oil and almond milk (since I was making this for C who isn't currently eating nuts). And I absolutely had to decrease the sugar-- this version is perfectly sweet for our taste (which is more like the Japanese version of sweetness).   I've been cutting wheat flour with gluten-free flours in order to decrease the gluten load (C has a threshold after which he gets gluten headaches), so thus the rice flour in addition to the wheat flour. Rice flour is sandy and chewy which is a great fit for this cake.  This is vegan and nut-free (FYI- from reading around the internet, coconut is typically not considered a nut, but a drupel?).

CAKE

Dry:
155 g wheat flour
100 g brown rice flour
1/8 C sugar
1.5 tsp baking soda
0.5 tsp kosher salt
1 tsp cinnamon
1/2 tsp nutmeg

Wet: blend in a blender:
1/2 banana
1 C water
1 TB white wine vinegar (or use apple cider vinegar)
vanilla extract

Topping: combine by mashing with a fork
1/4 C rice flour
1/8 C sugar
1 tsp cinnamon
2 TB cold coconut oil
pinch salt


Combine dry and wet ingredients in a bowl. Add 1 C blueberries (I thawed frozen blueberries by soaking in hot water in a mug, then draining the water off).

Pour batter into an 11x7" pyrex baking pan.  Crumble the topping over, distributing evenly over the surface of the batter.

Bake at 350 F for 30-45 minutes (??) until it is done.  (sorry I didn't take good measurements of the time on this one).