Preheat oven to 400 degrees F. Line cupcake tin with cupcake liners.
In a large bowl, combine the flour, sugar, cinnamon, salt, and baking powder and mix well.
Form a well in the flour mixture and add the mashed banana, canola oil, soymilk, and vanilla extract. Gently mix together with a fork or spoon. Fold in the diced apple chunks.
Prepare your crumb topping. Add the flour, sugar, cinnamon, and salt to a small bowl and mix well. Cut in the cold butter. To do this, slice the butter into small pieces with a knife, add it to the bowl, and then using a fork, mash the butter in with the dry mixture until combined. If necessary, you may use your hands briefly to combine, but you don't want the butter to warm and melt. The resulting crumb topping should be crumbly just barely sticking together when squeezed.
Fill your cupcake liners with batter (all the way to the top, which should make 10 muffins). Top with crumb topping, pushing it firmly into the top of the batter so it adheres to the muffin.
Bake for 27-30 minutes, or until the muffins start to get lightly golden on top and a toothpick comes out of the center of the muffin clean. Remove from oven and allow to cool before enjoying!
