|Butter (for the pan)|
|2||teaspoons baking powder|
|1/2||cup (1 stick) unsalted butter, at room temperature|
|1||teaspoon vanilla extract|
|1||tablespoon grated lemon rind|
|Juice of 1 lemon|
|1 1/2||cups fresh blueberries, picked over for stems and leaves|
|Extra sugar (for sprinkling)|
2. In a bowl, sift the flour, salt, and baking powder; set aside.
3. In an electric mixer, cream the butter and sugar. Gradually add the egg whites and mix until blended. Beat in the vanilla, lemon rind, and lemon juice.
3. With the mixer set on its lowest speed, beat the flour mixture into the batter alternately with the milk.
4. Remove the bowl from the mixer stand, and use a rubber spatula to fold in the berries. Divide the batter among the muffin cups and sprinkle the tops with sugar.
5. Set the muffins on the sheet. Bake for 20 to 25 minutes or until they are golden, turning the pan halfway through baking. Leave to cool in the pan for a few minutes, then turn out onto a wire rack to cool completely. Rebecca Dalzell