01 -
Rub lemon zest into sugar with fingers until fragrant to boost flavor.
02 -
Whisk flour and baking powder into the sugar-zest mixture.
03 -
Add eggs, melted butter, and milk. Mix gently, being careful not to overmix.
04 -
Gently fold frozen blueberries into the batter to avoid bleeding color.
05 -
Set the oven temperature to 210°C (410°F).
06 -
Line a muffin tin and fill each cup ¾ full with batter.
07 -
Top each muffin with 1 tbsp of blueberry jam and swirl using a toothpick.
08 -
Bake at 210°C (410°F) for 13 minutes, then lower the temperature to 170°C (340°F) and bake for an additional 8 minutes.
09 -
Allow muffins to cool in the tin for 5 minutes, then transfer to a rack. Serve warm or at room temperature.