Blend butter with macaroon mix in medium bowl.
Press one quarter of mixture firmly and evenly in bottom of 8-inch cake dish.
Set remaining mixture aside.
Prepare cake mix according to package directions.
Pour half the batter into cake dish.
Sprinkle one quarter of macaroon mixture evenly over batter, making sure it goes all the way to the edge.
MICROWAVE 4 MINUTES to 4 MINUTES, 30 SECONDS on HIGH, or until a wooden pick inserted in center comes out clean.
Turn out on cake rack.
Prepare and bake second layer.