A complex made up of consecutively stacked flat sheets, characterized in that it is configured for forming a package in a single run, preferably for containing food products, wherein said complex comprises: • at least a first die cut flat sheet configured for being folded, comprising a continuous first rim (10.1) demarcated by an outer contour (10.1.1) and an inner contour (10.1.2), wherein said inner contour (10.1.2) comprises a first portion (10.1.2.1) and the outer contour (10.1.1) comprises first (10.1.2.1) a second portion (10.1.1.1), said and second (10.1.1.1) portions corresponding with one another; o wherein said at least first die cut flat sheet further comprises at least a first main flap (10.2) extending along the first portion (10.1.2.1) of the inner contour (10.1.2) in the direction opposite the second portion (10.1.1.1) of the outer contour (10.1.1), the first main flap (10.2) being configured for forming a wall (1.3) of the package; and • an assembly comprising at least one additional flat sheet, wherein at least one of the at least one additional flat sheet of the assembly is a second die cut flat sheet configured for being folded, comprising a second rim (20.1) the outer contour (20.1.1) of which demarcates its perimeter, wherein said at least a second die cut flat sheet further comprises: - at least a second main flap (20.2) configured for forming a base of the package, said complex being characterized in that: the perimeter of any of the at least one additional flat sheet is demarcated by the first rim (10.1) of the first flat sheet such that it is kept within the confines of the inner (10.1.2) and outer (10.1.1) contours of the first flat sheet. • at least a first die cut flat sheet configured for being folded, comprising a continuous first rim (10.1) demarcated by an outer contour (10.1.1) and an inner contour (10.1.2), wherein said inner contour (10.1.2) comprises a first portion (10.1.2.1) and the outer contour (10.1.1) comprises first (10.1.2.1) a second portion (10.1.1.1), said and second (10.1.1.1) portions corresponding with one another; o wherein said at least first die cut flat sheet further comprises at least a first main flap (10.2) extending along the first portion (10.1.2.1) of the inner contour (10.1.2) in the direction opposite the second portion (10.1.1.1) of the outer contour (10.1.1), the first main flap (10.2) being configured for forming a wall (1.3) of the package; and o wherein said at least first die cut flat sheet further comprises at least a first main flap (10.2) extending along the first portion (10.1.2.1) of the inner contour (10.1.2) in the direction opposite the second portion (10.1.1.1) of the outer contour (10.1.1), the first main flap (10.2) being configured for forming a wall (1.3) of the package; and • an assembly comprising at least one additional flat sheet, wherein at least one of the at least one additional flat sheet of the assembly is a second die cut flat sheet configured for being folded, comprising a second rim (20.1) the outer contour (20.1.1) of which demarcates its perimeter, wherein said at least a second die cut flat sheet further comprises: - at least a second main flap (20.2) configured for forming a base of the package, - at least a second main flap (20.2) configured for forming a base of the package,