01 -
Combine flour, brown sugar, cold cubed butter, cinnamon and salt in a bowl. Use a fork or pastry cutter to cut the butter into the dry ingredients until pea-sized crumbs form. Refrigerate while making the cookie dough.
02 -
In a large bowl, beat the softened butter with brown sugar and granulated sugar until light and fluffy, about 2-3 minutes. Beat in the egg and vanilla.
03 -
Whisk together flour, baking powder and salt in a separate bowl. Gradually mix the dry ingredients into the wet ingredients until just combined, being careful not to overmix.
04 -
Very gently fold in the fresh blueberries, trying not to break them up too much.
05 -
Portion out rounds of dough and place them spaced apart on a parchment-lined baking sheet. Use a spoon or piping bag to dollop some blueberry jam onto the tops of each dough round, then use a knife or toothpick to gently swirl it into the tops.
06 -
Remove the streusel from the fridge and generously top each dough round with streusel crumbs, gently pressing them in.
07 -
Bake at 375°F for 12-15 minutes, until lightly golden but still quite soft in the middles.
08 -
Allow to cool completely before enjoying. These are phenomenal served slightly warm with a glass of cold milk to dunk them into.