Chocolate Chip Rice Krispie Cookies – Simmer + Sauce

Ingredients

• 1 cup, plus 1 tablespoon unsalted butter, softened and divided
• 1 1/4 cups sugar
• 2/3 cup brown sugar
• 1 egg
• 1 teaspoon vanilla extract
• 1 1/2 cups all-purpose flour
• 1/2 teaspoon baking powder
• 1/4 teaspoon baking soda
• 1 teaspoon kosher salt
• 2 1/2 cups Rice Krispies
• 1 1/4 cup semi-sweet chocolate chips
• 1 cup marshmallows, melted