This tam has a grid of squares / diamonds on the top (skipping some as to approximate a circle) and then a plain underside.

The headband is optional if you want a more classic beret style.

This pattern is possible to do in a single skein of yarn but you can optionally do the headband in a separate colour.

Note: This pattern does not provide instructions on how to do a normal Bavarian stitch, only how to convert it into a circle and a tam / beret.