• Preheat the oven to 400 degrees Fahrenheit (200 degrees Celsius). Line a 9 or 10-inch springform pan with parchment paper or spray with nonstick spray and set aside.

Streusel

• Combine flour, granulated sugar, and brown sugar in a small bowl. Pour in the melted butter whisk together with a fork. Chill in the fridge while you make the muffin cake batter.
  90 grams all purpose flour, 85 grams granulated sugar, 65 grams brown sugar light or dark, 70 grams unsalted butter

Cake

• In a large mixing bowl, whisk the remaining granulated sugar, brown sugar, melted butter, oil, eggs, and vanilla extract together until well combined.
  200 grams granulated sugar, 50 grams brown sugar, 56 grams unsalted butter, 50 grams vegetable oil, 2 large eggs, 1 teaspoon vanilla extract
• Next, whisk in the Greek yogurt and buttermilk until smooth with no lumps.
  120 grams plain Greek yogurt, 120 grams buttermilk
• Add the all purpose flour, baking powder, cinnamon, and salt to the wet ingredients. Gently fold with a rubber spatula, scraping around the sides of the bowl until just a few dry patches of flour are left.
  320 grams all purpose flour, 1 tablespoon baking powder, 1 teaspoon ground cinnamon, ½ teaspoon salt
• Toss the blueberries in a little flour and fold them into the batter until the dry streaks of flour disappear.
  296 grams blueberries
• Pour the batter into the springform pan. Evenly sprinkle the streusel on top of the cake batter.
• Bake for 5 minutes at 400°F (200°C), then reduce the heat to 350°F (180°C) and bake for 45-60 minutes or until a toothpick inserted in the center comes out clean with a few moist crumbs.
• Remove from oven and let cool in the pan for 10 minutes. Gently run a butter knife between the edges of the cake and the pan to loosen the sides and remove the outer ring. Let cool to room temperature on a wire rack, then slice and enjoy!