1First of all, divide up your berries into three different batches - set aside a 2/3 cup portion for mashing, then divide the remaining berries into two equal portions - one portion for folding into the batter, and the remainder for dropping on top.
2Preheat oven to 400 degrees F.
3Grease 6 jumbo muffins tins or 12 regular size muffin tins well.
4Combine flour, baking powder, salt, and cinnamon.
5In another bowl, on high speed with an electric mixer, cream the butter about 2 minutes- until light and fluffy.
6With the mixer still running, gradually add the sugar and mix well.
7Add the eggs, one at a time, mixing well.
8Continue to beat until creamy and batter looks light yellow.
9Mix in vanilla and mashed berries until well combined.
10Lower speed of mixer to medium, beat in some of the flour mixture, then some of the milk, and then more flour etc- in three portions each.
11Beat batter until airy and well combined, about 1 more minute.
12Gently fold in one of the portions of whole berries.
13Fill muffing tins almost all the way full.
14Drop the remaining portion of whole berries individually atop the muffin batter.
15Bake about 1o minutes, then REDUCE oven temp to 375 F and continue baking until golden brown and set in the center, about 15 minutes.