1️⃣ Prep & Preheat
Preheat oven to 350°F (175°C).
Grease a 9-inch springform pan (or line a 9x9" baking dish with parchment).
2️⃣ Make the Cream Cheese Filling
Beat cream cheese, sugar, egg yolk, and vanilla until smooth. Set aside.
3️⃣ Make the Cake Batter
Whisk flour, baking powder, baking soda, and salt in a bowl.
In another bowl, cream butter + sugar until fluffy.
Beat in eggs, sour cream, and vanilla.
Gradually mix in dry ingredients until just combined.
Gently fold in blueberries.
4️⃣ Assemble the Layers
Spread 2/3 of the batter into the pan.
Dollop cream cheese mixture on top, then swirl gently with a knife.
Drop remaining batter in spoonfuls over the cream cheese.
5️⃣ Add the Crumb Topping
In a bowl, mix flour, sugars, and cinnamon.
Cut in cold butter until crumbly.
Sprinkle evenly over the batter.
6️⃣ Bake & Cool
Bake 45-55 mins until a toothpick comes out clean.
Cool 20 mins before slicing (if you can wait that long!).
Pro Tips for the Best Cake
🔹 Room temp ingredients = smoother batter.
🔹 Don’t overmix – Keeps the cake tender.
🔹 Use frozen blueberries? Toss in 1 tbsp flour to prevent sinking.
🔹 Storage: Keep covered at room temp for 2 days or refrigerate for 5 days.
Serving Suggestions
☕ With coffee or tea – The ultimate pairing!
🍦 À la mode – Vanilla ice cream takes it over the top.
🌿 Garnish – Fresh mint or lemon zest for brightness.