1. Position the shelves in the upper and lower thirds of the oven. Heat the oven to 375F. Line the muffin pans with paper or foil cupcake liners.

2. In a large bowl, thoroughly whisk together the flour, baking powder, salt and baking soda. Set aside. Cut the butter into 1-inch pieces and place in the bowl of an electric mixer fitted with the paddle attachment. Add the lemon zest and blend on medium speed until smooth and lightened in color, about 1 minute.

3. Add the sugar in a steady stream, then blend in the egg and vanilla, scraping down the side of the bowl as needed. Reduce the mixer speed to low and add the flour mixture alternately with the buttermilk, dividing the flour into three parts and the buttermilk into two, starting and ending with the flour.

4. Mix just until blended after each addition. Portion half scoops of the batter into the prepared pans using a no. 16 ice cream scoop (1/4 cup capacity). Make a layer of blueberries placed evenly over the batter, then place a dollop of batter on top of the blueberries. It’s okay for the berries to show. Take a handful of the streusel topping and crumble it over the batter and berries completely covering the top with the crumbs. Press gently to adhere. Brush any stray crumbs from the top of the muffin pans using a small pastry brush.

5. Bake for 25 to 30 minutes or until the streusel topping is golden brown. To ensure even baking, towards the end of baking time, rotate the pans top to bottom and front to back. Remove from the oven and place on a rack to cool.