01 -
In a skillet over medium heat, melt the butter while stirring until it foams, turns amber, and develops brown solids at the bottom. Once golden and fragrant, remove from heat and transfer to a bowl to cool for 20 minutes. If still warm, chill in the freezer for 10 minutes to prevent excess cookie spreading.
02 -
In a bowl, sift together flour, cornstarch, baking soda, baking powder, and salt. Set aside.
03 -
In a large bowl, combine the cooled brown butter, granulated sugar, and brown sugar. Stir until smooth, then mix in eggs and vanilla extract.
04 -
Gradually fold the dry ingredients into the wet mixture until just combined.
05 -
Wrap the dough in plastic wrap and refrigerate for at least 1 hour.
06 -
While the dough chills, combine blueberries, sugar, and lemon juice in a saucepan. Cook on medium heat, stirring until thickened, approximately 30 minutes. Set aside to cool.
07 -
Preheat the oven to 175°C (350°F). Line a baking sheet with parchment paper. Scoop 3 oz balls of dough and place them 2 inches apart on the sheet. Bake for 12 minutes or until the edges are golden and the centers remain soft.
08 -
Let the cookies rest for 1-2 minutes, then press the center of each cookie with a small glass or shot glass to create a well. Spoon the prepared blueberry jam into each well, filling it to the top. Serve and enjoy.