Keto Vanilla Birthday Cake (1.7 carbs - tastes like REAL cake!)

Ingredients

• 2 cups almond flour
• 2 tablespoons oat fiber
• 1/4 cup unflavored whey protein isolate
• 1 tablespoon baking powder
• 1/2 teaspoon salt
• 6 egg whites, room temperature
• 1/2 cup unsalted butter, melted
• 1/3 cup plain Greek yogurt or sour cream
• 1 cup sugar-free sweetener
• 1 tablespoon vanilla extract
• 1/4 cup unsweetened nut or seed milk
• 2 cups unsalted butter, softened room temperature
• 1 1/2 cups powdered sugar-free sweetener
• 1 1/2 tablespoons vanilla extract
• 1/4 cup heavy cream