Name: Miracle Caramel Frosting
Total time: 3 h 40 min
Ingredients: 1 1/2 cups packed (10½ ounces/298 grams) dark brown sugar; 1/4 teaspoon baking soda; 1/4 cup (1¼ ounces/35 grams) all-purpose flour; 3 tablespoons cornstarch; 1/2 teaspoon salt; 1 1/2 cups whole milk; 2 teaspoons vanilla extract; 24 tablespoons unsalted butter, softened (3 sticks), cut into 24 pieces

Why This Recipe Works

Our approach to Miracle Caramel Frosting was unconventional, but the result was fluffy, flavorful icing the likes of which we’d never tasted. We started by heating and stirring flour and milk into a thick paste, beating together sticks of butter with granulated sugar, adding the paste, and continuing to beat until the mixture came together. To firm the icing and make it more spreadable, we adjusted the ratio of milk to flour and substituted cornstarch for some of the flour. The original recipe left little lumps of flour suspended in the icing. Adding sugar before heating the flour and milk mixture helped solve this problem. Straining the mixture before cooking it eliminated any residual lumps. Adding the butter to the paste a little at a time prevented the icing from resembling overbeaten whipped cream.

Before You Begin

Whole milk makes the richest, tastiest frosting. Use a stand mixer; the frosting is too thick for a hand mixer. And plan ahead, as the frosting needs time to cool.

Instructions

COOK MILK BASE Combine sugar, baking soda, flour, cornstarch, and salt in medium bowl. Slowly whisk in milk until smooth. Pour mixture through fine-mesh strainer into medium saucepan. Cook over medium heat, whisking constantly, until mixture boils and is very thick, 5 to 7 minutes. Transfer milk mixture to clean bowl and cool to room temperature, about 2 hours.

MAKE FROSTING With stand mixer fitted with whisk attachment, beat cooled milk mixture and vanilla on low speed until combined, about 30 seconds. Add butter, 1 piece at a time, and beat until incorporated, about 2 minutes. Increase speed to medium-high and beat until frosting is light and fluffy, about 5 minutes. Let sit at room temperature until stiff, about 1 hour.

make ahead

Frosting can be refrigerated in airtight container for 1 week. When ready to use, let stand at room temperature until softened, about 2 hours. Beat with stand mixer on medium-high speed until light and fluffy, about 1 minute.