Sprinkle Sheet Cake

Soft and buttery vanilla sheet cake filled to the brim with sprinkles. Topped with my favorite creamy vanilla frosting and, as expected, more sprinkles. This recipe requires a 12×17 half sheet jelly roll pan.

Ingredients

• 1 cup (16 Tbsp; 226g) unsalted butter, softened to room temperature
• 2 cups (400g) granulated sugar
• 2 large eggs, at room temperature
• 2 and 1/2 teaspoons pure vanilla extract
• 1/2 cup (120g) sour cream or plain yogurt*
• 2 and 1/4 cups (281g) all-purpose flour (spooned & leveled)
• 1 teaspoon baking soda
• 1/2 teaspoon salt
• 1 cup (240ml) whole milk*
• 1/2 cup (94g) rainbow sprinkles, plus more for decoration*

Vanilla Frosting

• 3/4 cup (12 Tbsp; 170g) unsalted butter, softened to room temperature
• 3 cups (360g) confectioners’ sugar
• 2–3 Tablespoons (30-45ml) whole milk*
• 2 teaspoons pure vanilla extract
• 1/8 teaspoon salt

Instructions

1. Preheat oven to 350°F (177°C). Generously grease and lightly flour a 12×17-inch half sheet/jelly roll pan. Set aside.
2. In a large bowl using a handheld mixer or stand mixer fitted with a paddle attachment, cream the softened butter for about 1 minute on medium speed. Get it nice and smooth, then add the sugar on