Preheat the oven to 375° F. Grease or line the wells of a 12-cup muffin pan with muffin liners. Toss the strawberry pieces with the extra tablespoon of flour in a small bowl and set it aside. **Note: This recipe makes 14 muffins, not 12.
Make the Streusel: Mix the flour, light brown sugar, ground cinnamon, and salt. Add the melted butter and stir until crumbly. Refrigerate until ready to use.
Make the Cream Cheese Filling: Using an electric mixer, beat the softened cream cheese, sugar, and vanilla extract until light and fluffy.
Make the Muffin Batter: Combine flour, granulated sugar, ground cinnamon, baking powder, baking soda, and salt in a medium bowl.
Whisk the {cooled} melted butter, eggs, milk, and vanilla extract in a large bowl. Add the flour mixture to the milk mixture and stir until a batter forms. Fold in the strawberries.
Fill the lined muffin cups ⅔ of the way full with muffin batter. Make a small crater in the center of each batter-filled cup using a spoon. Transfer the cream cheese mixture to a piping bag—pipe about 2 teaspoon of the cream cheese filling into the center of each unbaked muffin. Top each muffin with the remaining batter. Sprinkle the top of the muffins with streusel.
Bake muffins in the preheated oven until golden brown, and when a toothpick is inserted into the center of each muffin comes out clean or with a few crumbs.
Allow muffins to cool for about 10 minutes before transferring them to a wire rack to cool completely.