1 day in advance, make mane. Knead 1/2 teaspoon of Gum-Tex into 4 oz. red fondant. Using 9 in. fondant roller, roll out fondant 1/8 in. thick. Using pattern and knife, cut out mane. Let dry on dusted lightly cornstarch-dusted cake board for 2 days.
Bake cake. Bake and cool one layer 2-in. high cake. Prepare buttercream icing according to recipe. Using spatula, ice cake lightly to prepare for fondant covering.
Cover cake. Roll out yellow fondant 1/8 in. thick and cover cake. Also using patterns and knife, cut out tail from yellow fondant, rolled 1/8 in. thick. Reserve tail.
Add details to cake. Add details to cake. Roll out black fondant, 1/16 in. thick. Using the smooth side of the E of double sided round cutter, cut out two eyes. Using smooth side of F double oval cutter, cut out nose. Roll out to lengthen slightly.
Position lion mane on cake and attach with dots of icing.
Attach eyes and nose using a damp brush. Roll out a 1/4 in. ball of white fondant to 1/16 in. thick. Using narrow end of tip 10, cut out two dots and attach to eyes with damp brush for highlights.
Add tail. Roll out 1 oz. brown fondant, 1/8 in. thick. Using pattern and knife, cut out end of tail end. Position tail parts to cake on board with damp brush