Brush butter and flour mixture over the inside of 2 cake pans, 10 inches (25 cm) in diameter, or coat the pans with cake pan spray. Reserve.
Place the eggs, sugar, and salt in mixer bowl. Heat over simmering water to about 110°F(43°C), whipping continuously. Remove from the heat and whip at high speed until the mixture has cooled, is light and fluffy, and has r