Preheat the oven to 325 degrees F/163 degrees C. Line an square 8x8 baking pan with parchment paper that hangs over the sides and set it aside.
In a small bowl, grate the apples with a cheese grater. Measure out the 2 cups of apples and discard any extra juice. Set the bowl aside.
2 cups grated red apples
In a large bowl, add the brown sugar and oil and use a rubber spatula to mix them together.
1 cup canola oil, 1 ½ cups light brown sugar
Add the room temperature eggs and vanilla extract and mix to combine them completely into the oil and sugar.
2 large eggs, room temperature, 2 teaspoon vanilla extract
Add the apples and mix to combine them into the batter.
2 cups grated red apples
Add the baking soda, salt, and cinnamon, and flour. Mix with a rubber spatula to combine, scraping to the bottom of the bowl until there are no more flour pockets.
2 teaspoon baking soda, 2 cups all-purpose flour, 1 teaspoon salt, 1 tablespoon cinnamon
Pour the apple batter into the prepared pan place it in the oven. Set a timer for 25 minutes. Meanwhile make the crumble topping.
In a small bowl, combine the flour, sugar, cinnamon, cornstarch and baking powder. Cut the butter into cubes and add it to the bowl. Work the butter into the flour with your hands until the streusel is crumbly. Place the bowl in the freezer until the timer goes off.
¼ cup all-purpose flour, ¼ cup light brown sugar, ½ teaspoon cinnamon, 1 teaspoon corn starch, ½ teaspoon baking powder, 3 tablespoon cold unsalted butter, cubed
When the timer goes off, carefully remove the cake from the oven and carefully sprinkle the streusel on top.
Once all of the streusel is added, place the cake back in the oven and continue baking for another 20-25 minutes, or until a tooth pick inserted into the middle comes out clean.
Place on a cooling rack to cool completely. When the cake is cool, make the vanilla glaze.
In a small bowl, add the powder sugar, milk and vanilla and whisk to combine. Drizzle the glaze over the cooled cake, cut into slices and enjoy!
⅓ cup powdered sugar, 1-2 teaspoon any milk, ¼ teaspoon vanilla extract or vanilla bean paste