• Preheat your oven to 180°C (350°F) if using a conventional oven. Grease an 8x8 inch square cake pan with a little butter or your favorite cake release, then line the bottom with parchment paper. Once that’s done, set it aside and get ready to b

Cinnamon Streusel

• In a bowl, mix together the light brown sugar, all-purpose flour, and cinnamon until everything is evenly combined and no big lumps remain.
• Pour in the melted butter and stir until the mixture comes together into a crumbly texture. Pop it in the fridge to chill while you make the cake batter.

Cake Batter

• Sift the flour, cornstarch, baking powder, baking soda, and salt into a bowl. Give it a quick whisk or mix with a fork until everything is well combined, then set it aside.
• In a large mixing bowl, combine the butter, oil, and white sugar. Using a hand or stand mixer on medium speed, beat for about two minutes until the mixture looks light and fluffy.
• Add the eggs one at a time, mixing on low speed after each addition until fully combined. Then mix in the vanilla and buttermilk on low speed until smooth. Don’t worry if the batter looks a little curdled, that’s completely fine! Scrape down the sides and attachments since the rest of the mixing will be done by hand.
• Now, gently fold the dry ingredients into the wet mixture using a spatula. Mix only until you no longer see big lumps or streaks of flour. Try not to overmix the batter.
• Take the chilled streusel out of the fridge. It should have firmed up a little. Break it apart with a spoon and then your hands until it looks like coarse sand with a few small lumps throughout.
• Pour half of the cake batter into your prepared cake pan and spread it out evenly with a spatula. Sprinkle half of the streusel evenly over the batter, making sure to cover as much of the surface as possible.
• Next, spoon the remaining batter gently over the streusel. The easiest way is to place spoonfuls around the center of the pan, letting them touch so there are no gaps. Then, carefully spread the batter outward toward the edges without pressing into the streusel layer (this helps keep the layers neat). Don’t stress if it’s not perfect, it’ll still taste amazing!
• Top the cake with the rest of the streusel, spreading it evenly so there are no bare spots. Give the pan a gentle tap on the counter to release any large air bubbles.
• Bake for about 35 minutes, or until a toothpick inserted into the center comes out clean or with just a few moist crumbs.
• Let the cake cool in the pan for about 20 minutes, then turn it out onto a wire rack. Flip it again onto your serving plate so it’s right-side up and ready to enjoy!

Vanilla Glaze

• While the cake is cooling, let’s make the vanilla glaze. In a small bowl, whisk together the powdered sugar, vanilla, and milk until you have a smooth, pourable glaze.
• When the cake is just slightly warm to the touch (no need to wait until it’s completely cooled), drizzle the glaze over the top. Slice, serve, and enjoy every sweet bite!