Using a food processor, fork, or your hands, combine the cold butter, flour, and confectioners' sugar in a bowl until it resembles breadcrumbs.

Keep in the fridge/chiller while you proceed with the other components.

In a small bowl, mix together the cream cheese and confectioners' sugar. Set aside while you prepare the muffin batter.

Preheat oven to 170°C. Prepare a muffin pan with muffin liners.

Mix in the blueberries with 2 tbsp of the flour and set aside.

In the bowl of a stand mixer fitted with the paddle attachment, combine cream cheese and butter until smooth, about 3 minutes.

Add sugar gradually and beat until lighter and fluffier.

Add eggs one at a time, beating well with each addition.

Add in the vanilla.

Add the flour and mix until just combined.

Add in buttermilk with mixer on low and mix until just incorporated.

Mix in the blueberries till well incorporated.

Spoon a tablespoon of the muffin batter into the muffin cups. Filling each cup only halfway.

Add cream cheese swirl to each muffin cup, followed by using another tablespoon of the batter to fill each cup.

Using a toothpick, swirl the batter and the cream cheese of each muffin together.

Top with the crumb topping and bake for about 20-25 minutes.