Meals to be served on the occasion of Walimah

When Rasulullah Salallahu Alaihi Wasallam celebrated the Walimah of Safiyya Radiallahu Anha, then dates, cheese and ghee was served. [Bukhari]

When the Walimah of Khadija Radiallahu Anha was celebrated, then either one or two camels were slaughtered, and the meat served. [As Seeratul Halabiyyah Pg.139 Vol.1]

The Walimah of Aisha Radiallahu Anha was celebrated with milk that was sent by Hadrat Sa’ad Bin Ubadah Radiallahu Anhu in a large bowl.

The Walimah of Umme Salamah Radiallahu Anha was celebrated with dates and ghee. [Re:- Fathul Baari Pg.239 Vol.9]

On the occasion of the Walimah of Zainub Bint Jahsh Radiallahu Anha, a goat was slaughtered. The meat was served with roti. According to one narration, Umme Sulaim Radiallahu Anha had prepared some Halwa. The commentators have reconciled between the two narrations by stating that, initially meat and roti was served. Thereafter, Anas Radiallahu Anhu brought the Halwa, so it was eaten after the main course. [Re:- Fataawa Darul Uloom Zakariyya Pg.861 Vol.3]

In conclusion, you may serve any food that is easily available for Walimah. You should not incur unnecessary expenses in celebrating the Walimah.