Container, forming tool, and method for forming a container

A method of manufacturing a container for holding and heating a food product, the method comprising:

• obtaining a blank comprising a central portion, an outer edge, and a marginal portion between the outer edge and the central portion, the blank comprising a radius extending from a center of the blank to the outer edge, the marginal portion comprising a plurality of radial score lines having an angular spacing between respective adjacent radial score lines, the blank having a first thickness;
• positioning the blank in a forming tool;
• closing the forming tool comprising compressing the blank;
• and
• forming a container having a bottom panel, at least one side panel extending upwardly from the bottom panel, and a flange extending laterally outward from an upper edge of the at least one side panel, wherein the forming the container comprises:
• forming a cavity by upwardly folding the side panel relative to the bottom panel, and
• forming a plurality of pleats at the radial score lines, each pleat extending in the flange and extending into at least a portion of the at least one side panel, and
• compressing each pleat to a second thickness along the entire radial length of the flange from the upper edge of the at least one side panel to a free edge of the flange and compressing each pleat to a third thickness that is different than the second thickness along the at least a portion of the side panel, the second thickness being approximately two times the first thickness and the second thickness being greater than the third thickness, each pleat being radially spaced apart from an adjacent pleat by a portion of the flange having a thickness that is less than the second thickness.