01 -
Coat a 9×9-inch pan with grease or non-stick cooking spray.
02 -
In a large saucepan, melt the butter over medium heat. Stir in the brown sugar and vanilla essence until well combined. Add the oats and cook gently for 2-3 minutes, stirring occasionally.
03 -
Firmly press half of the oat mixture into the bottom of the greased pan, creating the crust. Set the other half aside for later.
04 -
In another saucepan, melt the chocolate chips and peanut butter together over low heat, stirring constantly until smooth.
05 -
Spread the melted chocolate and peanut butter mixture evenly over the oat crust in the pan.
06 -
Sprinkle the remaining oat mixture over the chocolate layer and press down gently to secure it.
07 -
Cover the pan and refrigerate the bars for at least 2-3 hours, or overnight, until firm. Allow the bars to come to room temperature before cutting them into squares.