01 -
In a large pot, melt unsalted butter over medium-low heat, stirring constantly. Add mini marshmallows, continuing to stir until the mixture is smooth and fully melted.
02 -
Remove the pot from heat. Immediately fold in the Rice Krispies cereal, stirring gently to coat evenly. Carefully add fresh blueberries, mixing gently to maintain their shape.
03 -
Lightly grease a 9x9-inch pan or line with parchment paper. Transfer the mixture to the pan and press it gently and evenly with a greased spatula or hands. Do not compact the mixture excessively.
04 -
Allow the pan to cool at room temperature for approximately 30 minutes, until the treats are set.
05 -
In a bowl, whisk together powdered sugar, milk, and vanilla extract until smooth. Add additional milk by the teaspoon if a thinner consistency is desired.
06 -
Drizzle the glaze over the cooled treats using a spoon or piping bag. Allow glaze to set for 10 to 15 minutes before slicing and serving.