Preparation

• Preheat the oven to 200°C with the rack in the center.
• Prepare a 12-cup muffin tin, lining only 10 cups; grease the top of the pan and add paper liners.
• Cream the butter and vegetable shortening with the paddle attachment for 1 minute.
  4 tablespoons unsalted butter, 4 tablespoons vegetable shortening
• Add the sugar and beat on medium speed for about 1 minute.
  200 g sugar
• Add the eggs one at a time on medium speed, then beat for about 2 minutes 30 seconds to incorporate air.
  2 eggs
• Add the vanilla extract and beat briefly.
  1 teaspoon vanilla extract
• Set aside about 75 g of the blueberries, crush them, and reserve.
  375 g frozen blueberries
• Pour off some of the juice released by the remaining blueberries, about 60 ml, leaving a little behind.
• Sprinkle the whole blueberries with 2 tablespoons of flour taken from the mixture, then toss to coat.
  120 g cake flour
• Combine the two flours, the salt, and the baking powder.
  130 g bread flour, 0.5 teaspoon salt, 2 teaspoons baking powder
• Alternately add the flour mixture and the milk, with the mixer running, mixing just until incorporated.
  120 ml whole milk
• With the mixer off, fold in the crushed blueberries, then the whole blueberries with their juice.
• Divide the batter among the 10 cups using an ice cream scoop, forming generously rounded tops.
• Sprinkle the tops of the muffins with the 2 tablespoons of sugar.
  2 tablespoons sugar
• Bake immediately for 5 minutes at 200°C.
• Reduce the temperature to 190°C and continue baking for 20 minutes, being careful not to overbake.
• Let cool on a wire rack.
• Carefully loosen the muffins from the pan.