In advance: Prepare base board. Using pan as guide, cut board 1 3/4 in. larger on all sides. Tint 48 oz. of fondant blue, roll out 1/8 in. thick and imprint design using Imprint Mat. Cover base board .
Use tip 2 and dark brown royal icing to pipe in imprint design. Work from outer edge of frame and in 2 1/4 in. from edge. Do not pipe in area where cross cake will be positioned. Let dry.
Bake and cool cake. Prepare and cover with rolled fondant. Tint remaining fondant light blue; roll out 1/4 in. thick. Cut out cross shape using top area of pan as pattern. Brush back with damp brush and attach. Score lines across center using edge of spatula.
Roll out dark brown fondant from Multi Pack 1/8 in. thick. Cut 1/2 in. wide strips for center cross, 11 and 7 in. long. Attach. Imprint lines. Position cake on base board. Pipe tip 4 white bead bottom border in buttercream.