-
1
Center a rack in the oven; preheat oven to 375u00b0.
-
2
Butter or spray the 12 molds in a regular-size muffin pan or fit the molds with paper muffins cups.
-
3
Alternatively, may use a silicone muffin pan, which needs neither greasing nor paper cups.
-
4
Place the muffin pan on a baking sheet.
-
5
Streusel-add flour, brown sugar, and allspice to a bowl; sift them through our fingers to blend.
-
6
Add the bits of cold butter and toss to coat, then use your fingers to work the butter into the dry ingredients until you've got irregularly shaped crumbs.
-
7
Set aside in the refrigerator for the moment (you can make the crumbs up to 3 days ahead and keep them covered in the refrigerator).
-
8
Muffins-in a bowl, whisk together the flour, sugar, baking powder, allspice, and salt.
-
9
Stir in the brown sugar, making certain there are no lumps.
-
10
In a large glass measuring cup or another bowl, whisk the melted butter, eggs, milk, and vanilla together until well combined.
-
11
Pour the liquid ingredients over the dry ingredients and, with the whisk or rubber spatula, gently but quickly stir to blend.
-
12
Don't worry about being thorough--the batter will be lumpy, and that is just as it should be.
-
13
Stir in the lemon zest, if using.
-
14
Divide the batter evenly among the muffin cups.
-
15
Sprinkle some streusel over each muffin, then use your fingertips to gently press the crumbs into the batter.
-
16
Bake for about 20 minutes, or until the tops are golden and a thin knife inserted into the center of the muffins comes out clean.
-
17
Transfer the pan to a rack and cool for about 5 minutes before carefully removing each muffin from its mold.
