In advance, tint fondant yellow. Knead 2 teaspoons Gum-Tex into 24 oz. of fondant; cover and reserve remaining fondant. Make 27 medium and 23 small ribbon roses. Roll out fondant 1/16 in. thick. Cut 1 x 6 in. long strips for medium and small roses. Begin rolling fondant strips lightly from one end, gradually loosening as flower gets larger; fold cut edge under. Pinch bottom to gather and secure. Trim flower bottom to desired height with scissors. Make extras to allow for breakage. Let dry in mini muffin pan dusted with cornstarch.