St. Patrick's Day Cake Recipe - How To Make A St. Patrick's Day Cake

Ingredients

• Cooking spray
• 5 1/2 c. (660 g.) all-purpose flour
• 1 tbsp. baking powder
• 1 tsp. kosher salt
• 3 c. (600 g.) granulated sugar
• 1 c. (2 sticks) unsalted butter, softened
• 1 c. vegetable oil
• 6 large eggs
• 1 tbsp. pure vanilla extract
• 1 c. whole milk
• 1 c. sour cream
• Red, orange, yellow, green, blue, and purple food coloring, for decorating
• 8 c. (920 g.) powdered sugar
• 2 1/2 c. (5 sticks) unsalted butter, softened
• 1/3 c. heavy cream
• 2 tsp. pure vanilla extract
• 1/4 tsp. kosher salt
• 1 1/2 c. Lucky Charm marshmallows
• Green, black, and yellow food coloring, for decorating