Add the butter and brown sugar to a small saucepan. Heat over medium heat, stirring constantly, until the sugar dissolves. Remove from heat, stir in vanilla extract, and let stand until room temperature.
1/2 cup unsalted butter, 1/3 cup light brown sugar, 1 teaspoon vanilla extract
Beat together the cream cheese and powdered sugar until smooth. Slowly add in the cooled butter mixture letting each addition fully incorporate before adding more. Let the mixer run for about 1 minutes.
8 ounces cream cheese, 1/2 cup powdered sugar
Fold in the mini chocolate chips, mini M&Ms and 1/2 of the candy monster eyes. Transfer to bowl and refrigerate for 1 hour. Before serving, add remaining monster eyes to the top of the dip.
1/2 cup mini chocolate chips, 1/4 cup mini M&Ms, 1/2 cup candy monster eyes