In a bowl add butter, powdered sugar, sugar, and vanilla.
Mix until butter is slightly whipped.
Add milk and continue mixing. Set aside.
Cereal & Milk Bars
In a bowl mix together cereal, oat flour, and salt until cereal is well coated. Set aside.
In another bowl add butter, honey, brown sugar, and vanilla extract. Microwave for 1 minute until butter is melted. Pour butter mixture over cereal and mix until cereal is coated throughout.
Line an 8x8 baking pan with parchment paper. Pack down 1/2 of the cereal mix to the bottom of pan.
Spread milk filling on top of cereal layer. Pack down the rest of cereal mixture on top and and refrigerate again 20 minutes. Cut into bars and serve.