Gooey Tres Leches-Frosted Avalanche Cake You Won't Want To Share

Name: Tres Leches-Frosted Avalanche Cake
Yield: 0
Ingredients: 3 eggs; 2 tablespoons butter; 1 cup sugar; 1 cup milk; 2 cups flour; 1 tablespoon baking powder; 1 can sweetened condensed milk; 1/2 cup butter, room temperature; 1/2 cup heavy cream; 1 1/4 cups powdered milk, divided