Step 1

Crumb topping, if desired:Whisk together flour, brown sugar, salt, and cinnamon in a bowl. Pour in melted butter and toss with a flexible spatula until large crumbs form.

Step 2

Muffins:Preheat oven to 375 degrees. Line standard 12-cup muffin tins with paper liners.

Step 3

Sift together flour, baking powder, and salt into a bowl.

Step 4

With an electric mixer on medium speed, cream together butter and granulated sugar until fluffy.

Step 5

Add eggs and vanilla; mix until well combined. Reduce speed to low; alternate adding reserved flour mixture and milk, beginning and ending with flour. Gently fold in blueberries by hand.

Step 6

Divide batter evenly among prepared cups; if desired, sprinkle generously with granulated sugar and mace. Alternatively, sprinkle crumb topping evenly over batter in each cup.

Step 7

Bake, rotating tins halfway through, until light golden on top, about 30 minutes. Cool in tins on wire racks 15 minutes before turning out muffins. Serve warm or at room temperature.