Ingredients:

  • 2 cups (250g) all-purpose flour
  • 1 tbsp (8g) cornstarch
  • 3/4 cup (150g) granulated sugar
  • 2 tsp (10g) baking powder
  • 1/2 tsp (3g) salt
  • 1/2 cup (115g) unsalted butter, melted and cooled
  • 2 large eggs, room temperature
  • 1/2 cup (120ml) sour cream
  • 1/4 cup (60ml) whole milk
  • 1 tsp (5ml) vanilla extract
  • 1 1/2 cups (225g) fresh blueberries
  • 1 tsp flour (for tossing blueberries)
  • 4 oz (115g) full-fat cream cheese, softened
  • 2 tbsp (25g) granulated sugar
  • 1 tbsp (15g) all-purpose flour
  • 1 large egg yolk, room temperature
  • 1/2 tsp (2.5ml) vanilla extract
  • 1/4 cup (30g) all-purpose flour
  • 1/4 cup (50g) brown sugar, packed
  • 2 tbsp (30g) cold unsalted butter, cubed
  • Pinch of salt

Instructions:

  1. Preheat oven to 400°F (200°C) and line a 12-cup standard muffin tin with paper liners.
  2. In a large bowl, whisk together flour, cornstarch, sugar, baking powder, and salt.
  3. In a medium bowl, whisk together melted butter, eggs, sour cream, milk, and vanilla until smooth.
  4. Pour wet ingredients into the dry ingredients. Using a spatula, fold until almost combined, leaving a few streaks of flour. Gently fold in the blueberries (tossed in flour).
  5. Beat softened cream cheese and sugar until smooth; mix in egg yolk, flour, and vanilla until thick and glossy. Transfer to a piping bag or Ziploc bag with the corner snipped.
  6. Fill each muffin cup 1/3 full with batter. Pipe approximately 1 generous tablespoon of cream cheese mixture into the center.
  7. Top with more batter until the cup is 3/4 full, ensuring the filling is completely covered.
  8. Rub together the streusel flour, brown sugar, cold butter, and salt with fingers until crumbly, then sprinkle over the muffin tops.
  9. Bake on the center rack for 22-25 minutes until the tops are mahogany-colored and a toothpick inserted into the cake portion comes out clean.